QCS 2010 Section 19 Part 1 General Page 1 1. GENERAL ...................................................................................................... 2 1.1 INTRODUCTION ........................................................................................... 2 1.1.1 1.1.2 Scope References 1.2 REGULATIONS AND STANDARDS.............................................................. 2 1.2.1 1.2.2 Qatar General Electricity & Water Corporation Compliance with Standards 1.3 CONTRACTOR’S RESPONSIBILITY ............................................................ 2 1.3.1 1.3.2 1.3.3 1.3.4 1.3.5 1.3.6 General Approval to Carry Out Plumbing Works Registration of Plumbers and Plumbing Contractors Notice of Intent Existing Services Maintenance Period Requirements 1.4 CRAFTSMEN................................................................................................. 3 1.4.1 1.4.2 Workmanship Qualifications 1.5 MATERIALS................................................................................................... 3 1.5.1 General 1.6 DRAWINGS ................................................................................................... 3 1.6.1 1.6.2 1.6.3 1.6.4 Explanation of Project Drawings Shop Drawings Co-ordination Drawings Record Drawings 1.7 SITE WORKS ................................................................................................ 4 1.7.1 1.7.2 1.7.3 1.7.4 1.7.5 Openings Painting Co-operation with other Trades. Protection of Finish Clean-Up 1.8 OPERATION AND MAINTENANCE MANUALS ............................................ 5 1.8.1 General Requirements 2 2 2 2 2 3 3 3 3 3 3 3 4 4 4 4 5 5 5 5 5 Qatar Project Management QCS 2010 2 2 QCS 2010 Section 19 Part 1 General Page 2 GENERAL 1.1 INTRODUCTION 1.1.1 Scope 1 This Section specifies the requirements for the construction and installation of all works associated with the supply, storage and distribution of potable water, with the exception of those works normally undertaken by the Qatar General Electricity & Water Corporation (QGEWC). 1.1.2 References 1 Related Sections are as follows:Section 1 Section 9 General Mechanical and Electrical 1.2 REGULATIONS AND STANDARDS 1.2.1 Qatar General Electricity & Water Corporation 1 The Contractor shall conform to all the requirements of the “Rules and Regulations for Plumbing Works” as prepared by QGEWC. 1.2.2 Compliance with Standards 1 It is required that certain products, components and materials covered in this Section comply with the provisions of particular standards (e.g. British Standards). Where there is a conflict between a particular referenced standard and the requirements of QGEWC, the latter shall prevail. 2 The Contractor shall conform to any requirements QGEWC may have with respect to ensuring that products, components and materials comply with any referenced standard. Such requirements may include, but not be limited to, samples, test results and supporting documentation. 1.3 CONTRACTOR’S RESPONSIBILITY 1.3.1 General 1 The Contractor is responsible for obtaining all necessary approvals and permits required to complete the Works. 1.3.2 Approval to Carry Out Plumbing Works 1 Approval to carry out plumbing works must be obtained from QGEWC for new installations and extensions or alternations to existing installations. 2 All approval procedures shall be as required by QGEWC. 1.3.3 Registration of Plumbers and Plumbing Contractors 1 All plumbers and plumbing contractors shall be approved by QGEWC. 2 All QGEWC water supply works shall be carried out by a contractor or sub-contractor prequalified and approved by the QGEWC. Proof of such approval shall be required in writing QCS 2010 Qatar Project Management 1. QCS 2010 Section 19 Part 1 General Page 3 prior to the Works commencing on Site and the name of any sub-contractor to be used shall be entered in the appropriate forms when the tender is submitted. Notice of Intent 1 The Contractor shall notify QGEWC in writing at least 14 days prior to the commencement of any plumbing works. 2 During the course of the Works, QGEWC or its nominated representative shall have full access to the Works. 1.3.5 Existing Services 1 The Contractor is responsible for locating and identifying all existing services in the area of the work or likely to be affected by the Work. 1.3.6 Maintenance Period Requirements 1 The Contractor is responsible for all the maintenance period requirements for all parts and components of the Works covered in this Section. Such requirements shall include, but not be limited to, the requirements of the Project Documentation and the manufacturer’s recommendations. 1.4 CRAFTSMEN 1.4.1 Workmanship 1 Construction of each part of the Works covered in this Section shall be undertaken by experienced craftsmen capable of performing the tasks allocated to them in a professional and competent manner. 2 If required by the Engineer, the Contractor shall instruct craftsmen to demonstrate their ability to perform tasks allocated to him. 1.4.2 Qualifications 1 Where the Project Documentation specifies that specialist craftsmen are required to undertake a specific work task, the Contractor shall furnish the Engineer with copies of qualifications pertinent to performing such work tasks for those craftsmen who will be undertaking the work. 1.5 MATERIALS 1.5.1 General 1 All materials, components and products shall comply with the relevant provisions of Section 1, General, subject to the provisions of Clause 1.2.2 of this Part. 2 All materials, components and products shall be supplied by experienced and approved manufacturers as designated in the Project Documentation and to the written approval of the Engineer. 1.6 DRAWINGS 1.6.1 Explanation of Project Drawings 1 For purposes of clearness and legibility, the Project Drawings are essentially diagrammatic, and although size and location of equipment are drawn to scale where possible, the QCS 2010 Qatar Project Management 1.3.4 QCS 2010 Section 19 Part 1 General Page 4 Contractor shall make use of all data in all of the Contract Documents and shall verify this information prior to and during construction. Scale and figure dimensions are approximate and are for estimating purposes only. Before proceeding with any part of the Work, the Contractor shall assume all responsibility for the fitting of his materials and equipment to other parts of the Works. 3 All work not shown in complete detail shall be installed in conformance with accepted standard practice and manufacturer’s recommendations. 4 All items shall be installed in a manner and in locations avoiding all obstructions, preserving headroom and keeping openings and passageways clear. Changes shall be made to the location of equipment and materials as may be necessary in order to accomplish this. 5 The drawings are essentially diagrammatic to the extent that many offsets, beds, traps, special fittings and exact locations are not indicated. The Contractor shall carefully study the drawings and premises in order to determine the best methods, exact locations, route, building obstructions, etc., and shall install all apparatus and equipment in the available locations. 6 Work indicated on drawings, but not mentioned in Specifications, or vice versa, shall be performed as if specifically mentioned or indicated by both. Any supplementary labour or materials required for a complete, approved, and properly operating installation shall be furnished by the Contractor. 1.6.2 Shop Drawings 1 The Contractor shall prepare shop drawings for all parts of the Works to be installed or constructed under this Section and submit them to the Engineer for approval. The shop drawings shall include diagrams, illustrations, schedules, general arrangements of equipment and appurtenances in relation to buildings and structures, method statements and details of specialised installation and construction work. 1.6.3 Co-ordination Drawings 1 These shall be prepared by the Contractor to show how interdisciplinary work will be coordinated. The location, size and details of fixings, box-outs, ducts, holes, pipe chases and plinths shall be shown on the detailed layout drawings which are co-ordinated with all other work disciplines. 1.6.4 Record Drawings 1 The Contractor shall prepare Record Drawings of all works constructed or installed under this Section. These shall be prepared as work proceeds. They shall provide a record of any modification to materials and equipment, and to the layout, arrangement and installation of the Works. 1.7 SITE WORKS 1.7.1 Openings 1 The Contractor shall co-operate with all trades in obtaining information as to openings required in walls, slabs and footings for all piping and equipment. Sleeves shall be accurately located and placed in forms before concrete is poured. Where several pipes pass through floors in close proximity, the Contractor may provide a single framed opening in lieu of individual sleeves. Framed openings shall be to the approval of the Engineer and shall be provided with 100 mm high curbs, on all sides. The Contractor shall pay all extra costs for cutting of holes as a result of incorrect, delayed or neglected locations of sleeves or frame openings. QCS 2010 Qatar Project Management 2 QCS 2010 Section 19 Part 1 General Page 5 Painting 1 All finished painting shall be done as specified in the Project Documents. All apparatus and equipment, not specified otherwise, shall be provided with a shop prime coat. All exposed ironwork, tanks pipes, and fittings without factory finish, including pipe hangers and rods shall be primed and painted with one coat of black asphalt varnish suitable for hot surfaces. Exposed pipe threads in bare or insulated piping shall be thoroughly cleaned and painted with two coats of metallic paint or red lead. 1.7.3 Co-operation with other Trades. 1 The Contractor shall so organise work progress to harmonise with the work of all trades so that work may proceed as expeditiously as possible. The Contractor shall be responsible for the correct placing of the Works and the connection thereof to the work of all related trades. 1.7.4 Protection of Finish 1 The Contractor shall provide adequate means for, and shall fully protect, all finished parts of materials and equipment against damage from whatever cause during the progress of the work and until final completion. All materials and equipment in storage and during construction shall be covered in such a manner that no finished surfaces will be damaged or marred and all moving parts shall be kept perfectly clean and dry. All damaged or defective work shall be replaced prior to applying for final acceptance. 1.7.5 Clean-Up 1 During the progress of work, premises shall be kept reasonably free of the debris, waste materials and rubbish resulting from work carried out under this Section. Upon completion and before final acceptance of the Works, all debris, temporary protective coverings, rubbish, left-over materials, tools and equipment shall be removed from the Site. Exposed piping, machinery and other apparatus shall be thoroughly cleaned of cement, plaster, paint and other materials; grease and oil spots shall be removed with cleaning solvent. Surfaces shall be carefully wiped and all cracks and corners scraped clean. Chromium or nickel plated materials and equipment shall be thoroughly polished. The entire installation shall be left in a neat, clean and usable condition. 1.8 OPERATION AND MAINTENANCE MANUALS 1.8.1 General Requirements 1 The Contractor shall prepare Operation and Maintenance Manuals for all mechanical, electrical and electronic equipment installed under this Section. 2 Operation and Maintenance Manuals shall conform to the requirements of Clause 1.1.4 of Section 9. END OF PART QCS 2010 Qatar Project Management 1.7.2 QCS 2010 Section 19 Part 2 Water Distribution Page 1 2. WATER DISTRIBUTION ............................................................................... 2 2.1 GENERAL ...................................................................................................... 2 2.1.1 2.1.2 2.1.3 Scope References Quality Assurance 2.2 WATER SYSTEMS ........................................................................................ 3 2.2.1 2.2.2 2.2.3 2.2.4 General Requirements Cold Water Systems Hot Water Systems Pressurised Systems 2.3 PUMPS .......................................................................................................... 4 2.3.1 2.3.2 2.3.3 2.3.4 2.3.5 General Requirements Lift Pumps Circulation Pumps Pipework Connections Control 2.4 WATER DISTRIBUTION PIPEWORK ........................................................... 5 2.4.1 2.4.2 2.4.3 General Requirements Pipe Materials Pipework Jointing 2.5 PIPE FIXINGS ............................................................................................... 6 2.5.1 2.5.2 General Requirements Spacing of Pipe Fixings 2.6 TAPS, VALVES AND PROTECTION DEVICES ............................................ 8 2.6.1 2.6.2 2.6.3 2.6.4 2.6.5 2.6.6 Draw-off Taps Drain Taps Ball Float Valves Servicing Valves Stopvalves Backflow Protection Devices 2.7 PIPE INSTALLATIONS ................................................................................ 11 2.7.1 2.7.2 2.7.3 2.7.4 General Requirements Pipework Expansion Pipe Sleeves Concealed Pipework 2.8 INSULATION OF WATER PIPES ................................................................ 12 2.8.1 2.8.2 General Application 2.9 MISCELLANEOUS ...................................................................................... 12 2.9.1 2.9.2 Electrical Work Related to Plumbing Works Water Meter Cabinet 3 3 3 4 4 5 5 5 5 5 5 6 6 6 8 9 9 9 10 10 11 11 11 11 12 12 12 12 Qatar Project Management QCS 2010 2 2 3 QCS 2010 Section 19 Part 2 Water Distribution Page 2 2. WATER DISTRIBUTION 2.1 GENERAL 2.1.1 Scope 1 This Part specifies the requirements for the installation, testing and commissioning of services supplying water for use within buildings. It covers the system of pipes, fittings and connected appliances installed to supply any building with water for ablutionary, cleaning, sanitary and laundry purposes. 2 Related Sections and Parts are as follows: Section 1 Section 9 General Cold Water Storage Hot Water Storage Commissioning of Systems General Mechanical and Electrical 2.1.2 References 1 The following standards are referred to in this Part: BS 864 ----- Capillary and compression fittings for copper tubes and copper alloy. BS 1010----- Specification for draw-off taps and stopvalves for water services (screwdown pattern). BS 1212----- Specification for float operated valves (excluding floats). BS 1394----- Stationary circulating pumps for heating and hot water service systems. BS 1968----- Specification for floats for ballvalves (copper). BS 1972----- Specification for polythene pipe (Type 32) for above ground use for cold water services. BS 2456----- Floats (plastics) for float operated valves for cold water systems. BS 2494----- Specification for elastomeric joint rings for pipework and pipelines. BS 2580----- Specification for underground plug cocks for cold water services. BS 2871----- Specification for copper and alloy tubes. BS 2879----- Specification for draining taps (screw-down pattern). BS 3505----- Specification for unplasticized polyvinyl chloride (PVC-U) pressure pipes for cold potable water. BS 3958----- Thermal insulating material. BS 4127----- Specification for light gauge stainless steel tubes. BS 4346----- Joints and fittings for use with unplasticized PVC pressure pipes. BS 4991----- Propylene copolymer pressure pipe. BS 5114----- Specification for performance requirements for joints and compression fittingsfor use with polyethylene pipes. BS 5154----- Specification for copper alloy globe, globe stop and check, check and gate valves. BS 5163----- Specification for predominantly key-operated cast iron gate valves for waterworks purposes. BS 5412----- Specification for the performance of draw-off taps with metal bodies for water services. BS 5413----- Specification for the performance of draw-off taps with plastics bodies for water services. BS 5422----- Method for supplying thermal insulating materials on pipes, ductwork and equipment BS 5433----- Specification for underground stopvalves for water services. BS 6144----- Expansion vessels using an internal diaphragm, for unvented hot water supply systems. QCS 2010 Qatar Project Management This Section Part 1 Part 4 Part 5 Part 6 QCS 2010 Section 19 Part 2 Water Distribution Page 3 BS 6281----- Devices without moving parts for the prevention of contamination of water by backflow. BS 6282----- Devices with moving parts for the prevention of contamination of water by backflow. BS 6283----- Safety devices for use in hot water systems. BS 6437----- Specification for polyethylene pipes (type 50) in metric diameters for general purposes. BS 6572----- Specification for blue polyethylene pipes up to nominal size 63 for bellow ground use for potable water. BS 6700----- Specification for design, installation, testing and maintenance of services supplying water for domestic use within buildings and their curtilages. BS 7671----- Requirements for electrical installations. 2.1.3 Quality Assurance 1 Items and equipment specified in this Part shall be provided by experienced and approved manufacturers and fabricators as designated in the Project Documentation or to the written approval of the Engineer. 2.2 WATER SYSTEMS 2.2.1 General Requirements 1 Internal hot and cold water supply installations shall be constructed so that water delivered is not liable to become contaminated to the extent that it is hazardous to health or is unfit for its intended use. 2.2.2 Cold Water Systems 1 Cold water systems shall be capable of providing cold water at the locations and in the quantities required and specified in the Project Documentation. 2 All cold water draw-off points shall be served via a cold water storage tank. The cold water storage tank will be served directly from the Qatar General Electricity & Water Corporation (QGEWC) supply mains. 2.2.3 Hot Water Systems 1 Hot water systems shall be capable of providing hot water at the locations, in the quantities and at the temperatures required and as specified in the Project Documentation. 2 To promote maximum economy of fuel and water the hot water distribution system should be designed so that hot water appears quickly at the taps when opened. To this end, dead legs should be as short as possible. The hot water pipe feeding a spray tap for hand washing should not exceed 1 metre in length. When draw-off points are situated at a distance from the hot water storage vessel, consideration should be given to the use of a separate water heater installed close to those draw-off points. When this is impracticable a secondary circuit with flow and return pipes to the storage vessel should be considered. Secondary circuits inevitable dissipate heat and should be avoided where possible QCS 2010 Qatar Project Management DIN 8079 --- Pipes made of chlorinated PVC DIN 8080 --- Pipes made of chlorinated PVC QCS 2010 Section 19 Part 2 Water Distribution Page 4 Pressurised Systems 1 Whether hot or cold water is involved, it shall be ensured that no part of the system bursts due to the hydraulic pressures to which it is subjected. The pressures in the system shall never exceed the safe working pressures of the component parts. The maximum working pressure in a sealed primary circuit shall not exceed 3 bar but it shall be capable of passing a test at 1.5 times the working pressure at the working temperature. The maximum working pressure in an unvented hot water storage vessel or secondary circuit shall not exceed 6 bar. 2 Where necessary the supply pressure shall be controlled by using an atmospheric break tank or pressure reducing valves. If the supply to a storage type water heater is through a pressure reducing valve of the type that permits backflow, the working pressure in the system shall be assumed to be the maximum pressure upstream of the valve. Where reliance is placed on pressure reducing valves to limit the maximum working pressure, these shall comply with BS 6283: Part 4. 3 Provision shall be made to accommodate expansion of water by one of the following alternative methods: (a) (b) (c) allow the expansion water to travel back along the cold feed pipe, provided that heated water cannot reach any communication pipe or branch feeding a cold water outlet where reverse flow along the cold feed is prevented by a stopvalve a with loose jumper, replace this valve by one with a fixed jumper where reverse flow along the cold feed is prevented, provide an expansion vessel in accordance with BS 6144 to accommodate expansion water. This vessel shall be sized in accordance with the volume of water heated and the water temperature rise so as to limit the pressure to the maximum working pressure for the system. The expansion vessel shall accommodate an expansion equal to 4% of the total volume of water heated. Any discharge from relief valves shall be readily visible and disposed of safely. 2.3 PUMPS 2.3.1 General Requirements 1 The installation of a pumped system should be undertaken by competent specialists experienced in such work. 2 Pumps shall be installed in accordance with the manufacturer’s recommendations and in an accessible location such that they may be readily maintained. 3 All pumps and associated equipment shall be capable of continuous operation in ambient 0 temperatures of up to 50 C. 4 Pumps shall be low speed and quiet in operation. 5 Pumps shall be firmly mounted. Measures to prevent vibration shall be taken where necessary. 6 No pump, required to increase pressure in or rate of flow from a supply pipe or any fitting or appliance connected to a supply pipe, shall be connected unless prior written approval from QGEWC is obtained. 7 Pumps located externally shall be provided with a suitable sun shade. QCS 2010 Qatar Project Management 2.2.4 QCS 2010 Section 19 Part 2 Water Distribution Page 5 Lift Pumps 1 Centrifugal pumps with electric motors shall be used. 2 The pumps may be either the vertical type or horizontal type and shall be directly coupled to their electric motors. 3 Pump capacity shall be as stated in the Project Specification. 4 Where the pumping system has duty and standby pumps, the pumps shall be used alternately. 2.3.3 Circulation Pumps 1 Circulating pumps shall comply with the relevant provisions of BS 1394: Parts 1 and 2. 2 Circulating pumps shall be suitably suppressed to prevent radio and television interference. 3 Pump capacity shall be as stated in the Project Specification. 2.3.4 Pipework Connections 1 Flexible connections shall be used so as to prevent the transmission of pump and motor noise via pipework. 2 All pipework connections to and from the pump shall be adequately supported and anchored against thrust. 3 Inlet and outlet pipework connections to lift pumps shall be fitted with gate valves complying with the relevant provisions Clause 2.10 of this Part. 4 Inlet and outlet pipework connections to circulating pumps shall be fitted with servicing valves complying with the relevant provisions Clause 2.9 of this Part. 2.3.5 Control 1 Pump control shall be as described in the Project Documentation. 2.4 WATER DISTRIBUTION PIPEWORK 2.4.1 General Requirements 1 Every pipe, pipe joint and connected fitting shall be capable of withstanding, without damage or deterioration, sustained temperatures of up to 40C for cold water installations and up to 70C, with occasional short-term peaks of up to 100C for heated water applications. 2 Pipes, pipe joints, pipe linings and connected fittings shall be made of materials that do not impart taste, colour, odour or toxicity to the water nor promote or foster microbial growth under the conditions where they are going to be installed. 3 If pipes, pipe joints or fittings are of dissimilar metals, measures shall be taken to prevent corrosion. Dissimilar metals shall be avoided in below ground installations. 2.4.2 Pipe Materials 1 Copper pipework shall comply with the relevant provisions of BS 2871: Part 1; underground pipes shall be to Table Y with a coating of seamless continuous PVC sheeting and above ground pipes shall be to Table X. Copper and copper alloy tube fittings should comply with the relevant provisions of BS 864: Part 1, Type B or BS 864: Part 2, Type A. QCS 2010 Qatar Project Management 2.3.2 QCS 2010 Section 19 Part 2 Water Distribution Page 6 The use and installation of polyethylene pipework shall comply with the relevant provisions of BS 1972 (above ground use), BS 6437 (general purposes) and BS 6572 (below ground use). Copper alloy tube fittings for polyethylene pipes shall comply with the relevant provisions of BS 864: Part 3. Joints for polyethylene pipes shall comply with the relevant provisions of BS 5114 and BS 3505. 3 The use and installation of polypropylene pipework shall comply with the relevant provisions of BS 4991 and shall be Series 1. 4 The use and installation of unplasticized PVC (PVC-U) pipework shall comply with the relevant provisions of BS 3505. Solvent welded joints and fittings for PVC-U pipes shall comply with the relevant provisions of BS 4346: Part 1. Mechanical joints and fittings for PVC-U pipes shall comply with the relevant provisions of BS 4346: Part 2. PVC-U pipework shall only be used for cold water applications. 5 The use and installation of chlorinated PVC (CPVC) pipework shall comply with the relevant provisions of DIN 8079 and DIN 8080. 6 Stainless steel pipework shall comply with the relevant provisions of BS 4127. 2.4.3 Pipework Jointing 1 Jointing of pipes shall be in accordance with the relevant provisions of BS 6700 2 All proprietary joints shall be made in accordance with the manufacturer’s instructions. 3 Care shall be taken to establish satisfactory jointing techniques for all water service pipework. All burrs shall be removed from the ends of the pipes and any jointing materials used shall be prevented from entering the water system 4 All piping and fittings shall be cleaned internally and be free from particles of sand, soil metal filings and chips etc. 5 Jointing systems using elastomeric sealing rings shall be Type W, complying with the relevant provisions of BS 2494, and shall be obtained from the pipe manufacturer. 2.5 PIPE FIXINGS 2.5.1 General Requirements 1 Copper and stainless steel piping shall be secured by clips or brackets made from copper or copper-alloy. 2 Steel piping shall be secured by clips or brackets made from steel, copper alloy or suitable plastic. Copper clips or brackets shall not be used for fixing steel piping. 3 PVC-U, polyethylene, polypropylene and CPVC piping shall be secured by clips or brackets made from suitable metal or plastic. Allowance shall be made for free lateral movement within the clips and brackets. 4 Piping that is insulated shall be secured on clips or brackets that allow sufficient space behind the back of the pipe and the batten or wall to which the pipe is fixed for the insulation to be properly installed. 2.5.2 Spacing of Pipe Fixings 1 The spacings for fixings for internally located piping shall be in accordance with Table 2.1, 2.2, 2.3 and 2.4 as applicable. The figures given are based on an ambient temperature of 20C. For other temperature ranges the pipe manufacturer should be consulted. QCS 2010 Qatar Project Management 2 QCS 2010 Section 19 Part 2 Water Distribution Page 7 Table 2.1 Maximum Spacing of Fixings for Internal Piping Type of Piping Spacing on horizontal run Spacing on vertical run (mm) (metres) (metres) Copper (light gauge) and 15 1.200 1.800 stainless steel complying with 22 1.800 2.400 BS 2871: Part 1 or BS 4127: 28 1.800 2.400 Part 2 35 2.400 3.000 42 2.400 3.000 54 2.700 3.000 76 3.000 3.600 108 3.000 3.600 133 3.000 3.600 159 3.600 4.200 Table 2.2 Maximum Spacing of Fixings for Internal Piping Type of Piping Nominal size of pipe Spacing on horizontal run Spacing on vertical run (mm) (metres) (metres) Copper (heavy gauge) 15 1.800 2.400 complying with BS 2871: Part 2 22 2.400 3.000 28 2.400 3.000 35 2.700 3.000 42 3.000 3.600 54 3.000 3.600 76 3.600 4.500 108 3.900 4.500 133 3.900 4.500 159 4.500 5.400 QCS 2010 Qatar Project Management Nominal size of pipe QCS 2010 Section 19 Part 2 Water Distribution Page 8 Table 2.3 Maximum Spacing of Fixings for Internal Piping Type of Piping Nominal size of pipe Spacing on horizontal run Spacing on vertical run (inches) (metres) PVC-U complying with BS 3505 0.530 1.060 and CPVC complying with DIN 1 0.610 1.220 8079 and 8080 3 /4 0.685 1.370 1 0.760 1.520 1 1 /4 0.840 1.680 1 1 /2 0.915 1.830 2 1.065 2.130 3 1.370 2.740 4 1.525 3.050 6 1.830 3.660 /8 /2 Tables 2.4 Maximum Spacing of Fixings for Internal Piping Type of Piping Polyethylene and polypropylene complying with BS 1972 or BS 4991 respectively Nominal size of pipe Spacing on horizontal run Spacing on vertical run (inches) (metres) (metres) /8 0.300 0.500 ½ 0.400 0.800 /8 0.400 0.800 1 0.400 0.800 1 1 /4 0.450 0.900 1 1 /2 0.550 0.900 2 0.550 1.100 1 2 /2 0.600 1.100 3 0.700 1.200 4 0.700 1.400 3 3 2.6 TAPS, VALVES AND PROTECTION DEVICES 2.6.1 Draw-off Taps 1 Metal bodied draw-off taps shall conform to the relevant provisions of BS 5412: Parts 1-5. 2 Plastic bodied draw-off taps shall confirm to the relevant provisions of BS 5413: Parts 1-5. QCS 2010 Qatar Project Management (metres) 3 QCS 2010 Section 19 Part 2 Water Distribution Page 9 Taps not fixed directly to an appliance shall be screwed into a suitable pipe fitting. 4 The fitting, or the pipe immediately adjacent to the tap, shall be firmly secured to a suitable support so as to prevent strain on the pipe and its joints when the tap is operated. 2.6.2 Drain Taps 1 Draining taps shall comply with the relevant provisions of BS 2879. 2 Draining tap shall be of the screwdown type with a removable key and shall be fixed over a drain or have provision for discharging the water to the nearest convenient point for disposal. 2.6.3 Ball Float Valves 1 Except for interconnected tanks arranged to store water at the same level, every pipe supplying water to a storage tank shall be fitted with a float operated valve or some other equally effective device to control the inflow of water and maintain it at the required level. The inlet control device shall be suitable for the particular application, taking into account the supply pressure and the temperature of the water in the cistern. 2 When a float operated valve is used it shall either: (a) (b) comply with BS 1212: Part 2 or 3 and be used with a float complying with BS 1968 or BS 2456 of the correct size corresponding to the length of the lever arm and the water supply pressure; or where any other float operated valve or other level control device is used, it shall comply with the performance requirements of BS 1212 where applicable to the circumstances of its use and shall be clearly marked with the water pressure, temperature and other characteristics for which it is intended to be used. 3 Every float operated valve shall be securely fixed to the cistern it supplies and where necessary braced to prevent the thrust of the float causing the valve to move and so alter the water level at which it shuts off. This water level shall be at least 25 mm below the lowest point of the warning pipe connection or, if no warning pipe is fitted at least 50 mm below the lowest point of the lowest over flow pipe connection 4 Every pipe taking water from a cistern of capacity exceeding 18 litres shall be fitted with a servicing valve close to the storage cistern, tank or cylinder. 5 Every ball float valve shall be so placed that it is readily accessibly for examination, maintenance and operation. 2.6.4 Servicing Valves 1 Servicing valves shall be located in accessible positions so as to enable the flow of water to individual or groups of appliances to be controlled and to limit the inconvenience caused by interruption of supply during repairs. 2 A servicing valve shall either comply with the requirements for stopvalves as specified in Clause 2.13 of this Part or shall be capable of withstanding a static pressure 1.5 times the maximum pressure it will be subjected to in use, be leaktight when closed against the latter pressure and, when installed on any pipe pressurised from the mains or on any pipe under a static pressure exceeding 1 bar, shall be operable only by means of a key, screwdriver or coin inserted into a slot on the valve. Screwdown servicing valves shall not be of loose jumper design. Copper alloy gate valves complying with the relevant provisions of BS 5154 may be used as servicing valves. 3 A servicing valve shall be fitted upstream of, and as close as practicable to, every float operated valve connected to a supply pipe. QCS 2010 Qatar Project Management 3 QCS 2010 Section 19 Part 2 Water Distribution Page 10 4 Pipes taking water from a storage tank of capacity exceeding 18 litres shall be fitted with a servicing valve. The valve shall be fitted as close to the storage tank as practicable. Pipes taking water from storage tanks with a capacity that does not exceed 18 litres shall not be fitted with servicing valves. 2.6.5 Stopvalves 1 The use and installation of stopvalves shall comply with the relevant provisions of BS 6700. 2 Stopvalves fitted to service pipes shall comply with the relevant provisions of the British Standards referenced in Table 2.5. Table 2.5 Nominal Size of Pipe 50 mm or smaller Standard Above Ground Below Ground BS 1010: Part 2 BS 2580 BS 2580 BS 5433 BS 5433 50 mm or larger BS 5163 BS 5163 3 Stopvalve components of fittings incorporating stopvalves shall comply with the requirements for stopvalves. 4 Stop valves shall be so placed that they may be readily inspected, operated and maintained. 5 When a stopvalve is installed on an underground pipe it shall be enclosed in a pipe guard or chamber under a surface box of the correct grade for the traffic loading relevant to the location. 2.6.6 Backflow Protection Devices 1 Every pipe through which water is supplied to a point of use or draw-off where backflow or backsiphonage is likely to occur shall be fitted with a backflow protection device. 2 Pipe interrupters for backflow protection shall comply with the relevant provisions of BS 6281: Part 3. 3 Vacuum breakers for backflow protection shall comply with the relevant provisions of BS 6282: Part 2 and 3. 4 Check valves for backflow protection shall comply with the relevant provisions of BS 6282: Part 1. Any additional installation instruction issued by the manufacturer or supplier of the check valve shall also be complied with. 5 Combined check valve and vacuum breaker for backflow protection shall comply with the relevant provisions of BS 6282: Part 4. 6 Double check valve assembly for backflow protection shall comply with the relevant provisions of BS 6282: Part 1, with a draining tap complying with the relevant provisions of BS 2879 connected between them. QCS 2010 Qatar Project Management Stopvalves Fitted to Service Pipes QCS 2010 Section 19 Part 2 Water Distribution Page 11 PIPE INSTALLATIONS 2.7.1 General Requirements 1 Pipe runs within buildings should not be laid exactly horizontal but to a slight fall to reduce the risk of air locks forming. 2.7.2 Pipework Expansion 1 In installations with limited straight runs and many bends and offsets, thermal movement is accommodated automatically. In installations that do not have limited straight runs and many bends and offsets, allowance for expansion and contraction of the pipes shall be made by forming expansion loops, by introducing changes of direction to avoid long straight runs or by fitting proprietary expansion joints. This is particularly important where temperature changes are considerable and where the pipe material has a relatively large coefficient of expansion. 2 The maximum length of a straight run for each different pipe material to be used shall be detailed in the Project Specification or shown on the Project Drawings. 2.7.3 Pipe Sleeves 1 Where a pipe enters a building it shall be accommodated in a sleeve that has previously been solidly built-in and the space between the pipe and the sleeve shall be filled with nonhardening, non-cracking, water-resistant material for a minimum length, of 150 mm at both ends to prevent the passage of water, gas or insects. 2.7.4 Concealed Pipework 1 Concealed pipework shall be housed in properly constructed builders work ducts or wall chases and have access for maintenance and inspection. 2 Ducts and chases should be constructed as the building structure is erected and should be finished smooth to receive pipe fixings. 3 No pipe or joint in or under a building shall be embedded in any wall or solid floor or in any material below a solid floor at ground level except for the following: (a) (b) (c) (d) the enclosing of any pipe and associated pipe joints in a purpose made duct or chase in a solid floor in such a way that the pipe and pipe joints can be exposed for purposes of examination, repair or replacement without endangering the structural integrity of the building the enclosing of any pipe and associated pipe joints in a purpose made chase in a solid wall (but not within the cavity of a hollow wall) in such a way that the pipe and pipe joints can either be capped off and isolated or be exposed for purposes of examination, repair or replacement without endangering the structural integrity of the building the enclosing of any pipe and associated pipe joints in any internal wall that is not a solid wall the enclosing of any pipe within a purpose made pipe sleeve or duct in or under any solid floor in such a way that the pipe may be removed and replaced; for pipes laid in such a way, there shall be an inspection access point at each joint. 4 No pipe or pipe joint shall be located under floorboards or a suspended floor, at ground floor level unless every pipe and pipe joint is accessible for examination. 5 Where access panels are formed in floor panels of structural chipboard or plywood, the structural stability of the building shall not be affected. 6 All pipe laid in ducts shall be adequately supported by clipping as specified in Table 2.1. QCS 2010 Qatar Project Management 2.7 QCS 2010 Section 19 Part 2 Water Distribution Page 12 INSULATION OF WATER PIPES 2.8.1 General 1 Thermal insulating materials shall comply with BS 5422 and BS 3958 where applicable. 2 Thermal insulating materials shall be applied in accordance with the manufacturer’s recommendations. They shall be kept dry before, during and after application, except for water which may be required for the purpose of mixing. Gaps shall not be left at the joints of the insulating materials. 3 Where necessary, the insulating material shall be resistant to, or protected by a suitable covering against, mechanical damage, rain, moist atmosphere, groundwater and vermin. 4 Examples of suitable materials of insulating purposes are: (a) polyurethane foam (b) foamed or expanded plastics (c) corkboard (d) amoliated vermiculite. 2.8.2 Application 1 While insulating material shall be continuous over pipes and fittings, it shall be finished in such a manner as to allow access to valves for operation. 2 Where cold water pipes pass through areas of relatively high dew point, e.g. habitable areas, they shall be insulated to prevent condensation forming on them. 3 Pipes in hot water supply systems that exceed the maximum lengths given in Table 2.6 shall be thermally insulated in accordance with BS 5422. Table 2.6 Maximum Permissible Lengths of Uninsulated Hot Water Pipes Outside diameter of pipes Maximum length (mm) (m) 12 20 Over 12 up to and including 22 12 Over 22 up to and including 28 8 Over 28 3 2.9 MISCELLANEOUS 2.9.1 Electrical Work Related to Plumbing Works 1 Electrical works related to plumbing works shall be done in accordance with the relevant provisions of BS 7671 and the requirements of QGEWC. 2.9.2 Water Meter Cabinet 1 Water meter cabinets shall comply with the Rules and Regulations Guide for Plumbing Works prepared by QGEWC. 2 Water meter cabinets shall be located in an easily accessible place as approved by QGEWC. END OF PART QCS 2010 Qatar Project Management 2.8 QCS 2010 Section 19 Part 3 Plumbing Pipework in Trenches Page 1 3. PLUMBING PIPEWORK IN TRENCHES ...................................................... 2 3.1 GENERAL ...................................................................................................... 2 3.1.1 3.1.2 Scope References 3.2 PIPES AND FITTINGS .................................................................................. 2 3.2.1 3.2.2 General Requirements Pipe Materials 3.3 PIPEWORK JOINTING .................................................................................. 3 3.3.1 General Requirements 3.4 PIPE LAYING................................................................................................. 3 3.4.1 3.4.2 3.4.3 3.4.4 3.4.5 3.4.6 3.4.7 3.4.8 3.4.9 3.4.10 3.4.11 General Bedding Concrete Protection to Pipes Completion of Pipe Surround Backfilling Protective Coatings Pipes under Buildings Avoidance of Contamination Restraint of Pipes Testing of Pipework Surface Boxes 2 3 3 3 4 4 5 5 5 5 6 6 6 6 Qatar Project Management QCS 2010 2 2 QCS 2010 Section 19 Part 3 Plumbing Pipework in Trenches Page 2 3. PLUMBING PIPEWORK IN TRENCHES 3.1 GENERAL 3.1.1 Scope 1 This Part specifies the requirements for pipes and fittings for below ground plumbing works. 2 Related Sections and Parts are as follows: Section 1 Section 5 General Water Distribution Commissioning of Systems General Concrete 3.1.2 References 1 The following standards are referred to in this Part: BS 743 BS 864 BS 882 BS 1142 BS 2494 BS 2871 BS 3505 BS 4127 BS 4346 BS 4772 BS 4991 BS 5114 BS 6076 BS 6572 BS 6700 Materials for damp-proof courses. Capillary and compression fittings for copper tubes and copper alloy. Aggregates from natural sources for concrete Fibre building boards Specification for elastomeric joint rings for pipework and pipeline. Specification for copper and alloy tubes. Specification for unplasticized polyvinyl chloride (PVC-U) pressure pipes for cold potable water. Specification for light gauge stainless steel tubes. Joints and fittings for use with unplasticized PVC pressure pipes. Ductile iron pipes and fittings. Propylene copolymer pressure pipe. Specification for performance requirements for joints and compression fittings of use with polyethylene pipes. Tubular polythene film for use as a protective sleeving for buried iron pipes and fittings. Specification for blue polyethylene pipes up to nominal size 63 for bellow ground use for potable water. Specification for design, installation, testing and maintenance of services supplying water supplying water for domestic use within buildings and their curtilages. 3.2 PIPES AND FITTINGS 3.2.1 General Requirements 1 Pipes shall have adequate strength to meet the loading requirements, be sufficiently robust to withstand site handling and be sufficiently durable to remain watertight for the anticipated life of the system. Pipes and joints should remain sufficiently water tight to prevent the ingress of ground water. 2 Every pipe, pipe joint and connected fitting shall be capable of withstanding, without damage or deterioration, sustained temperatures of up to 65C when operating under normal working pressures. QCS 2010 Qatar Project Management This Section Part 1 Part 2 Part 6 QCS 2010 Section 19 Part 3 Plumbing Pipework in Trenches Page 3 Pipe materials, fittings, linings and jointing materials shall impart no taste, colour, odour or toxicity to the water nor promote or foster the microbial growth under the conditions where they are going to be installed. 4 If pipes, pipe joints or fittings are of dissimilar metals, measures shall be taken to prevent corrosion. Contact between pipework components of dissimilar metals shall be avoided in below ground installations. 3.2.2 Pipe Materials 1 Copper pipework shall comply with the relevant provisions of BS 2871: Part 1, Table Y, coated with seamless continuous PVC sheeting. Copper and copper alloy tube fittings should comply with the relevant provisions of BS 864: Part 2. 2 The use and installation of polyethylene pipework shall comply with the relevant provisions of BS 6572. Copper alloy tube fittings for polyethylene pipes shall comply with the relevant provisions of BS 864: Part 3, Joints for polyethylene pipes shall comply with the relevant provisions of BS 5114 and BS 3505. 3 The use and installation of polypropylene pipework shall be in accordance with the relevant provisions of BS 4991 and shall be Series 1. 4 The use and installation of unplasticized PVC pipework shall comply with the relevant provisions of BS 3505. Solvent welded joints and fittings for PVC-U pipes shall comply with the relevant provisions of BS 4346: Part 1. Mechanical joints and fittings for PVC-U pipes shall comply with the relevant provisions of BS 4346: Part 2. 5 Ductile iron pipework shall comply with the relevant provisions of BS 4772. 6 Stainless steel pipework shall comply with the relevant provisions of BS 4127. 3.3 PIPEWORK JOINTING 3.3.1 General Requirements 1 Jointing of pipes shall be in accordance with the relevant provisions of BS 6700. 2 All proprietary joints shall be made in accordance with the manufacturer’s instructions. 3 Care shall be taken to establish satisfactory jointing techniques for all water service pipework. All burrs shall be removed from the ends of the pipes and any jointing materials used shall be prevented from entering the water system 4 All piping and fittings shall be cleaned internally and be free from particles of sand, soil metal filings and chips etc. 5 Jointing systems using elastomeric sealing rings shall be Type W, complying with the relevant provisions of BS 2494, and shall be obtained from the pipe manufacturer. 3.4 PIPE LAYING 3.4.1 General 1 Where socketed pipes are required to be laid on a granular or sand bed, or directly on a trench bottom, joint holes shall be formed in the bedding material or final excavated surface to ensure that each pipe is uniformly supported throughout the length of its barrel and to enable the joint to made. 2 Pipes shall be laid on setting blocks only where a concrete bed or cradle is used. QCS 2010 Qatar Project Management 3 QCS 2010 Section 19 Part 3 Plumbing Pipework in Trenches Page 4 Where pipes are required to be bedded directly on the trench bottom, the final excavated surface shall be trimmed and levelled to provide even bedding of the pipeline and shall be free from all extraneous matter that may damage the pipe, pipe coating, or sleeving. Where rock is encountered, the trench shall be cut at least 150 mm deeper than other ground and made up with well compacted selected fill material. 4 No protective cap, disc or other appliance on the end of a pipe or fitting shall be removed permanently until the pipe or fitting which it protects is about to be jointed. Pipes and fittings, including any lining or sheathing, shall be examined for damage and the joint surfaces and components shall be cleaned immediately before laying. 5 Suitable measures shall be taken to prevent soil or other material from entering pipes, and to anchor each pipe to prevent flotation or other movement before the Works are complete. 6 Where pipeline marker tape is specified, it shall be laid between 100 mm and 300 mm above the pipe. 3.4.2 Bedding 1 Bedding for pipes shall be constructed by spreading and compacting granular bedding material over the whole width of the pipe trench. After the pipes have been laid, additional material shall, if required, be placed and compacted equally on each side of the pipe, and where practicable, this shall be done in sequence with the removal of the trench supports. 2 Unless otherwise detailed in the Project Documentation, bedding material shall be in accordance with Table 3.1 Table 3.1 Bedding Material Pipe Diameter Bedding up to 65 mm Sand 65 - 100 mm 10 mm single sized aggregate 100 - 200 mm 10 or 14 mm single sized or 14-15 mm graded aggregate Over 200 mm 10, 14 or 20 mm single sized or 15-5 or 20-5 mm graded aggregate. 3 Nominal single sized aggregate and graded aggregate shall comply with Table No. 4 of BS 882. 4 Sand for bedding material shall comply with the relevant provisions of BS 882. 5 Bedding systems other than those specified above may be allowed upon approval of the Engineer or as recommended by the pipe manufacturer. 3.4.3 Concrete Protection to Pipes 1 Pipes to be bedded on or cradled with concrete shall be supported on precast concrete setting blocks. The top face of each block shall be covered with two layers of compressible packing complying with BS 743. 2 Concrete provided as a protection to pipes shall be Grade C20, placed to the required depth in one operation. QCS 2010 Qatar Project Management 3 QCS 2010 Section 19 3 Part 3 Plumbing Pipework in Trenches Page 5 Where pipes with flexible joints are used, concrete protection shall be interrupted over its full cross-section at each pipe joint by a shaped compressible filler of bitumen impregnated insulating board to BS 1142 or equally compressible material. The thickness of the compressible filler shall be in accordance with Table 3.2. Table 3.2 Thickness of Compressible Filler Thickness of compressible filler (mm) up to 300 13 Over 300 and up to 600 25 Over 600 and up to 1200 38 4 Rapid hardening cement shall not be used in concrete for the protection of plastics pipe. 5 Plastics pipes shall be wrapped with a layer of plastic sheeting complying with a composition in accordance with Clause 3 of BS 6076 and a nominal thickness of 125 microns before being surrounded by concrete. 6 Concrete work shall comply with the relevant provisions of Section 5, Concrete. 3.4.4 Completion of Pipe Surround 1 Fill material shall, where required, be placed and compacted over the full width of the trench in layers not exceeding 150 mm before compaction, to a finished thickness of 250 mm above the crown of the pipes. 3.4.5 Backfilling 1 Backfilling shall, wherever practicable, be undertaken immediately the specified operations preceding it have been completed. Backfilling shall not, however, be commenced until the parts of the Works to be covered have achieved a strength sufficient to withstand all loading imposed thereon. 2 Backfilling around existing structures shall be undertaken in such manner as to avoid uneven loading or damage. 3 Filling material to excavations shall be deposited in layers not exceeding 250 mm unconsolidated thickness and compacted to 95% modified proctor. 4 Where the excavations have been supported and the supports are to be removed, these, where practicable, shall be withdrawn progressively as backfilling proceeds in such a manner as to minimise the danger of collapse. All voids formed behind the supports shall be carefully filled and compacted 3.4.6 Protective Coatings 1 Coatings, sheathings or wrappings shall be examined for damage, repaired where necessary, and made continuous before trench excavations are backfilled. 3.4.7 Pipes under Buildings 1 Where a pipe has less than 300 mm of cover under a load bearing slab, it should be surrounded with concrete as an integral part of the slab. Where possible, the concrete surround shall be poured at the same time as the slab. The surround shall be tied to the slab with nominal steel reinforcement placed vertically with turned over ends. QCS 2010 Qatar Project Management Nominal bore of pipe (mm) QCS 2010 Section 19 Part 3 Plumbing Pipework in Trenches Page 6 No provision for pipe flexibility along the concrete surround shall be made, unless an expansion joint is included in the slab. A construction joint should be included in the surround at that point which must also coincide with a pipe joint. 3 In normal, stable ground conditions, and with 300 mm or more of cover to the pipeline beneath the slab, a total granular surround can be used as a pipe bedding. Refer to Clause 3.4.2 for bedding specification. 4 Flexibility shall be incorporated into the pipeline as it leaves any concrete surround. 5 Where plastic pipes are to be surrounded in concrete, Clause 3.4.3 of this Part shall be complied with. 3.4.8 Avoidance of Contamination 1 No pipe shall be laid or installed near a sanitary manhole, cesspool, septic tank, soakaway, refuse pit or other feature likely to cause the water to become contaminated and/or cause deterioration to the pipe material. 2 Any pipe that crosses over a sewer shall be laid so that there is at least 600 mm clearance between the pipe barrels. Any pipe that lies adjacent to a sewer shall be laid so that there is at least 3m between the barrels. Plumbing pipes shall not be laid below sewers. 3 Where the above criteria cannot be met, and with the approval of the Engineer in writing, the pipe shall be encased in concrete. The limit of the concrete encasement shall be determined on site by the Engineer. No breaks in the concrete encasement shall be made at joints. If the concrete encasement extends over one or more joints it shall be treated as a beam and reinforced appropriately; in such cases, the Contractor shall prepare reinforcement details with supporting calculations and submit them to the Engineer for approval. 4 Where it is necessary to determine the extent of contamination, the Contractor shall arrange for soil samples to be taken and tested. The locations at which soil samples are taken and the number of samples to be taken shall be determined by the Engineer. 3.4.9 Restraint of Pipes 1 Except where the method of jointing and normal trench backfill are adequate to prevent longitudinal movement, Grade C20 concrete thrust blocks cast in contact with undisturbed ground shall be constructed at changes in direction, junctions and blank ends. 2 Any additional excavation required to accommodate thrust blocks shall be carried out after the bend or branch is in position and the thrust face shall be trimmed back to remove all loose or weathered material immediately prior to concreting. 3 Thrust blocks shall be required to develop adequate strength before any internal pressure is applied to the pipeline. 4 Where plastic pipes are to be surrounded in concrete, Clause 3.4.3. of this Part shall be complied with. 3.4.10 Testing of Pipework 1 Pressure tests shall be carried out on below ground plumbing pipes. Test procedures are detailed in Part 6 of this Section. 3.4.11 Surface Boxes 1 Surface boxes shall be provided to give access to operate valves. END OF PART QCS 2010 Qatar Project Management 2 QCS 2010 Section 19 Part 4 Cold Water Storage Page 1 4. COLD WATER STORAGE............................................................................. 2 4.1 GENERAL ...................................................................................................... 2 4.1.1 4.1.2 4.1.3 4.1.4 Scope System Description Submittals Quality Assurance 4.2 TANK CONSTRUCTION................................................................................ 3 4.2.1 General Requirements 4.3 FILTERS ........................................................................................................ 4 4.3.1 General Requirements 3 4 Qatar Project Management QCS 2010 2 2 3 3 QCS 2010 Section 19 Part 4 Cold Water Storage 4. COLD WATER STORAGE 4.1 GENERAL 4.1.1 Scope 1 This Part specifies the requirements for cold water storage systems. Page 2 Related Sections and Parts are as follows: Section 1 General Water Distribution Commissioning of Systems General 4.1.2 System Description 1 Cold water storage tanks shall impart no taste, colour, odour or toxicity to the water nor promote or foster microbial growth under the conditions where the tank is going to be installed. 2 The tank shall be supported on a firm level base capable of withstanding the weight of the tank when filled with water to the rim. 3 Where possible and practicable, tanks shall be positioned in locations where they can be easily accessed for inspection, cleaning and maintenance. 4 Tanks positioned outside buildings shall be provided with a suitable shade. 5 Where two or more tanks are coupled together in series, the inlet and outlet shall be at opposite ends of the series. 6 Tanks shall not be buried or sunk in the ground without the prior approval from the Qatar General Electricity & Water Corporation (QGEWC). 7 Each tank shall be fitted with a 25 mm diameter outlet for connection to a washout pipe. The outlet shall be flush with the bottom of the tank. The floor of tank shall be laid at a slight fall towards the outlet. A washout pipe and a stop-tap shall be fitted to the outlet. The washout pipe shall be run to a point as detailed in the Documentation. 8 Every pipe supplying water to a cold water tank shall be fitted with a float operated valve or some other equally effective device, as detailed in Part 2 of this Section, to control the inflow of water and maintain it at the required level. The float valve shall be securely fixed to the tank and be installed so that the level of water in the tank when full under normal conditions is not less that 25 mm below the level of the warning or overflow pipe. A stopvalve complying with the relevant provisions of Part 2 of this Section shall be fitted to the pipework immediately upstream of the float valve to shut off supply of water to that valve. 9 Distribution pipes for tanks shall be connected so that the lowest point of the outlet is not less than 50 mm above the bottom of the tank. 10 Connections to distribution pipes feeding hot water apparatus shall be set at a level of at least 25 mm above connectors to pipes feeding cold water outlets. QCS 2010 Qatar Project Management This Section Part 1 Part 2 Part 6 QCS 2010 Section 19 Part 4 Cold Water Storage Page 3 Any tank with an effective capacity of up to 4500 litres shall be fitted with a warning type overflow pipe. Tanks with an effective capacity exceeding 4500 litres shall be fitted with one or more overflow pipes. For capacities exceeding 4500 litres, either the lowest pipe will be a warning type overflow pipe, or a device shall be fitted that gives an audible or visual alarm when water in the tank reaches a level at least 50 mm below the lowest point of the lowest overflow pipe. 12 The invert level of the overflow pipe shall be not less than 75 mm below the invert level of the inlet pipe. 13 Overflow pipes shall be made of a rigid corrosion resistant material. No overflow or warning pipe shall rise in level outside the cistern. 14 Warning type overflow pipes shall discharge water immediately the water in the tank reaches the overflow level and shall discharge to a conspicuous position; these shall be outside the building where appropriate. 15 The overflow pipe or pipes should be able to convey water away from the tank at a rate equal to or greater than the rate of flow of water into the tank. Notwithstanding, warning type overflow pipes shall be not be less than 20 mm in diameter. 4.1.3 Submittals 1 The Contractor shall provide manufacturers’ specifications for all items to be supplied under this Part. 2 The Contractor shall provide design calculations and shop drawings for the fabrication and erection of sectional type storage tanks, unless otherwise detailed in the manufacturer’s data sheets. 3 The Contractor shall provide design calculations and shop drawings for the fabrication and erection of tank support assemblies unless otherwise detailed in the manufacturer’s data sheets. 4 The submittal shall include catalogue pages, erection descriptions and manufacturer data. 5 Unless the positions of the discharges for the overflow pipes are described in the Project Documentation, the Contractor shall submit his proposals for their positioning to the Engineer for approval. 4.1.4 Quality Assurance 1 Fabricated cold water storage tanks and associated equipment shall be provided by experienced and approved manufacturers and fabricators as designated in the Project Documentation and to the written approval of the Engineer. 4.2 TANK CONSTRUCTION 4.2.1 General Requirements 1 Cold water storage tanks shall be constructed in accordance with the Rules and Regulations for Plumbing Works as prepared by QGEWC. 2 The tanks shall be constructed with one of the following materials/methods: (a) (b) (c) fibre glassed reinforced plastic GRP sectional panel reinforced concrete (underground storage). QCS 2010 Qatar Project Management 11 QCS 2010 Section 19 3 Part 4 Cold Water Storage Tanks smaller than 6m in length shall have a removable close-fitting vermin proof cover. Tanks greater than 6m in length shall have two or more securable manhole covers. 4.3 FILTERS 4.3.1 General Requirements 1 Filters shall be of a type as detailed in the Project Documentation. 2 As a minimum, filters shall be able to remove the following: harmful bacteria giardia cysts chlorine tastes and odours sediment to 1 micron. Filters shall have the following characteristics: (a) inhibit the growth of bacteria and other micro-organisms (b) easy to inspect, clean and maintain. 4 Filters shall not unduly affect distribution rates. END OF PART QCS 2010 Qatar Project Management (a) (b) (c) (d) 3 Page 4 QCS 2010 Section 19 Part 5 Hot Water Storage Page 1 5. HOT WATER STORAGE ............................................................................... 3 5.1 GENERAL ...................................................................................................... 3 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 5.1.6 5.1.7 Scope References System Description Identification Plate Submittals Safety Quality Assurance 5.2 HOT WATER STORAGE TANKS .................................................................. 4 5.2.1 5.2.2 Tank Construction Pressure and Non-Pressure Hot Water Storage Tanks 5.3 LOW CAPACITY ELECTRIC IMMERSION HEATER SYSTEMS .................. 5 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7 5.3.8 System Description Immersion Heaters Heating Element Pressure Relief Pipework Temperature and Temperature Control Electric Control Pilot Light 5.4 CALORIFIER SYSTEMS ............................................................................... 6 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6 5.4.7 5.4.8 5.4.9 5.4.10 5.4.11 System Description Storage Tank Construction Heat transfer System Tube Batteries Electric Heating Elements Calorifier Mountings Thermometers Altitude or Pressure Gauges Pressure Relief Valve Combined Pressure and Vacuum Gauges Vacuum Breaker 5.5 CISTERN TYPE WATER HEATERS ............................................................. 8 5.5.1 General Requirements 5.6 PRESSURE CONTROL ................................................................................. 8 5.6.1 General Requirements 5.7 VENTILATION ............................................................................................... 9 5.7.1 5.7.2 Storage Tanks Indirect Calorifier Systems 5.8 EXPANSION VESSEL ................................................................................... 9 5.8.1 General Requirements 4 4 5 5 5 5 5 5 5 6 6 6 6 7 7 7 7 7 7 8 8 8 8 9 9 9 Qatar Project Management QCS 2010 3 3 3 4 4 4 4 QCS 2010 Section 19 Part 5 Hot Water Storage Page 2 5.9 INSULATION ................................................................................................. 9 5.9.1 General 9 Qatar Project Management QCS 2010 QCS 2010 Section 19 Part 5 Hot Water Storage 5. HOT WATER STORAGE 5.1 GENERAL 5.1.1 Scope 1 This Part specifies the requirements for hot water storage systems. 2 Related Sections and Parts are as follows: Page 3 This Section: Section 1 General Water Distribution Commissioning of Systems General 5.1.2 References 1 The following standards are referred to in this Part: BS 21 BS 417 BS 699 BS 759 BS 853 BS 1566 BS 1780 BS 1894 BS 2871 BS 3198 BS 3274 BS 3456 BS 3599 BS 4213 BS 4504 BS 4814 BS 6144 BS 6282 BS 6283 Pipe threads for tubes and fittings where pressure tight joints are made on threads (metric dimensions) Galvanized mild steel cisterns and covers, tanks and cylinders Specification for copper direct cylinders for domestic purposes Valves, gauges and other safety fittings for applications to boilers and to piping installations for and in connection with boilers Calorifiers and storage vessels for central heating and hot water supply Copper indirect cylinders Bourdon tube pressure and vacuum gauges Design and construction of electric boilers of welded construction Copper and copper alloy. Tubes Specification for copper hot water storage combination units for domestic purposes Tubular heat exchangers for general purposes Specification for safety of household and similar electrical appliances Electrical controls for domestic appliances Cold water storage and combined feed and expansion cisterns (polyolefin of olefin copolymer) up to 500 litres capacity for domestic purposes Circular flanges for pipes, valves and fittings (PN designated) Expansion vessels using an internal diaphragm, for sealed hot water systems Expansion vessels using an internal diaphragm, for hot water unvented supply systems Devices with moving parts for the prevention of contamination of water by backflow Safety devices for use in hot water systems 5.1.3 System Description 1 Storage-type water heaters shall be used for the provision of hot water services. 2 The hot water storage tank shall be constructed so that water delivered is not liable to become contaminated to the extent that it is hazardous to health or unfit for its intended use. 3 The capacity of the storage tank shall be as stated in the Project Documentation. QCS 2010 Qatar Project Management Part 1 Part 2 Part 3 QCS 2010 Section 19 Part 5 Hot Water Storage Page 4 5.1.4 Identification Plate 1 All hot water storage tanks shall have an engraved or cast-metal identification plate clearly showing the following: (a) (b) (c) (d) (e) manufacturer’s name and address date of manufacture hydraulic test pressures maximum working pressure rated capacity and output Submittals 1 The Contractor shall provide manufacturers’ specifications for all items to be supplied under this Part. 2 The Contractor shall provide design calculations and shop drawings for the fabrication and erection of tank support assemblies (free standing or wall mounted), unless otherwise detailed in manufacturer’s data sheets. 3 The submittal shall include catalogue pages, erection descriptions and manufacturer’s data. 5.1.6 Safety 1 All safety requirements specified by the Qatar General Electricity & Water Corporation, the standard to which the hot water storage tank is constructed and the manufacturer shall be strictly adhered to. If the requirements specified by any of these three parties differ or conflict in any respect, the most stringent requirement, as defined by the Engineer, shall be followed. 5.1.7 Quality Assurance 1 Fabricated hot water storage tanks and associated equipment shall be provided by experienced and approved manufacturers and fabricators as designated in the Project Documentation and to the written approval of the Engineer. 5.2 HOT WATER STORAGE TANKS 5.2.1 Tank Construction 1 Hot water storage tanks constructed of copper shall comply with the relevant provisions of BS 699, BS 853, BS 1566 and BS 3198, as applicable. 2 Hot water storage tanks may be constructed of materials other than copper provided that they are corrosion resistant, glass lined or porcelain lined and provided that they are approved by the Qatar General Electricity & Water Corporation. Appropriate British Standards, or equivalent, specifying the construction of storage tanks covered in this paragraph shall be supplied by the Contractor to support the required approval. 3 Tanks shall incorporate replaceable, sacrificial magnesium anodes for cathodic protection if directed in the Project Documentation. 5.2.2 Pressure and Non-Pressure Hot Water Storage Tanks 1 The hot water tanks shall be non-pressure or pressure as directed in the Project Documentation. 2 Non-pressure hot water storage tanks shall have ventilation systems as described in Clause 5.7 of this Part. QCS 2010 Qatar Project Management 5.1.5 QCS 2010 Section 19 Part 5 Hot Water Storage Page 5 For non-pressure hot water storage tanks, no hose or other connection shall be made to the outlet of a non-pressure, storage type, water heater and under no circumstances shall the outlet be controlled by a tap or valve. 4 For pressure systems it shall be verified that the heater is suitable for the proposed supply pressure. 5 Suitable arrangements to accommodate expansion of the heated water shall be made for pressure hot water storage tanks. See Clause 5.8. 5.3 LOW CAPACITY ELECTRIC IMMERSION HEATER SYSTEMS 5.3.1 System Description 1 A low capacity (domestic) electrical immersion heater system involves an electric heating element placed within a hot water storage tank. Such heaters shall be used for the provision of hot water services for applications where the demand for hot water is small (i.e. kitchens and bathrooms, etc.). 2 Electric immersion heaters shall be of the vented or unvented type, as directed in the Project Documentation. 3 Tank construction shall be in accordance with Clause 5.2 of this Part. 5.3.2 Immersion Heaters 1 Electric immersion heaters shall comply with the relevant provision of BS 3456. 5.3.3 Heating Element 1 The material of the heating element shall be a high-grade stainless steel. Other materials with high corrosion resistance may be used if approved by the Engineer. 5.3.4 Pressure Relief 1 An expansion relief valve shall be fitted in the cold feed to the hot water storage tank and no valves (other than a drainage tap) shall be fitted between the expansion relief valve and the storage tank. The expansion or pressure relief valve setting shall be the maximum working pressure plus 0.5 to 1.5 bar. 5.3.5 Pipework 1 For tanks with a capacity of 25 litres or greater, the size of the hot water outlet pipe shall be smaller than the cold water inlet pipe. 5.3.6 Temperature and Temperature Control 1 Unless otherwise detailed in the Project Specification, the temperature of the stored water shall never exceed 65°C. 2 Every hot water storage tank shall be fitted with a thermostat acting on the heat input. In addition, every hot water storage tank of capacity greater than 150 litres shall be fitted with an automatic control capable of stopping and starting the heat input to the stored water at pre-set times. 5.3.7 Electric Control 1 All electrical controls, including thermostats, cut-outs and switches, shall comply with the relevant provisions of BS 3599. QCS 2010 Qatar Project Management 3 QCS 2010 Section 19 Part 5 Hot Water Storage Page 6 Pilot Light 1 The heater shall incorporate a clearly visible pilot light. 5.4 CALORIFIER SYSTEMS 5.4.1 System Description 1 Calorifier systems shall be used for hot water applications with a high hot water demand (hospitals, schools, etc.). 2 Calorifier systems shall be storage type systems and shall be the direct or indirect type. 3 Direct systems involve directly heating the water that will enter the hot water distribution system. This is done by circulating the water in the hot water storage tank through a heat transfer system (boiler). When inside the boiler, the water is directly exposed to the heat source. 4 Direct type systems shall be designed for gravity circulation. Flow and return pipes between the boiler and the storage tank shall run as directly as possible and shall be not less than 25 mm diameter. The storage tank shall be located at a sufficient height above the boiler to give adequate circulation. 5 Indirect systems involve heating water by means of routing steam or hot water through the hot water storage tank via a tube battery. A heat transfer system (boiler) heats up the water or generates the steam that is conveyed through the tube battery that runs through the water storage tank. On exiting the hot water storage tank, the tube returns to the boiler. The hot water/steam does not come into contact with the water that will enter the hot water distribution system. 6 Indirect systems shall incorporate a sealed or vented primary circuit as directed in the Project Documentation. Primary circuits comprise the boiler, the primary heat exchanger in the hot water storage tank and the interconnecting and associated pipework. 7 Calorifiers shall incorporate electrical immersion heaters if required by the Project Documentation. 5.4.2 Storage Tank Construction 1 Storage tank construction shall be in accordance with Clause 5.2 of this Part and shall be horizontal or vertical type. 2 The storage tanks shall comply with the relevant provisions of BS 853 Grade B for shell o operating pressures not exceeding 4.5 bar and temperatures not exceeding 90 C. 3 They shall be supported on fabricated feet attached to the shell or on separate cradles or frames. Sheet lead pads shall be fitted between shell bearing surfaces and any separate supports. 4 They shall have screwed and/or flanged connections complying with the relevant provisions of BS 21 and BS 4504. 5 They shall be delivered with all connections capped or blanked-off. 5.4.3 Heat transfer System 1 Boilers shall comply with the relevant provisions of BS 1894 unless otherwise specified in the Project Documentation. QCS 2010 Qatar Project Management 5.3.8 QCS 2010 Section 19 Part 5 Hot Water Storage Page 7 Tube Batteries 1 Tube battery shall be design shall comply with the relevant provisions of BS 3274 Type 2. 2 Tubes batteries shall be of solid drawn copper to BS 2871 Part 3. 3 Tube batteries shall be fixed or removable, as stated in the Project Documentation. If fixed type tube batteries are to be used, the storage tank shall include an access opening for battery maintenance purposes. 5.4.5 Electric Heating Elements 1 Electric immersion heaters shall be complete with an integral thermostatic controller. 2 A minimum of two heating elements shall be provided in each calorifier. The first shall be at low level and the second one approximately two thirds from the base. The ratings of the elements shall be such that the lower heating element shall provide a minimum heat-up time of two (2) hours. The higher heating element shall be equivalently rated for a heat up time of four (4) hours. 3 The material of the heating element shall be a high-grade stainless steel. Other materials with high corrosion resistance may be used if approved by the Engineer. 5.4.6 Calorifier Mountings 1 The calorifiers shall have connections for hot water system controls and for open systems, a vent pipe connection. 2 The calorifiers shall also have an emptying/drain cock of the bronze gland pattern with hose union connection and malleable iron lever handle. The cock shall be fitted to the calorifier shell lowest point to ensure complete removal of water content and shall be of adequate size (25 mm diameter minimum). 5.4.7 Thermometers 1 The calorifier shall incorporate a stainless steel dial type mercury thermometer. The dial shall o be 100 mm diameter (minimum), white faced with a black figured scale calibrated from 0 C o o o to 120 C with divisions at 1 C intervals and numbered at 10 C intervals with bold figures. The thermometer shall be complete with an integral vertical or centre stem and separate pocket to suit the immersion position. 5.4.8 Altitude or Pressure Gauges 1 The calorifier shall incorporate a stainless steel dial type altitude or pressure gauges. The dial shall be 100 mm diameter (minimum), white faced with a black figured scale, calibrated both in bar and metre head, to approximately twice the working pressure, complete with lever handle gauge cock and adjustable red dial pointer set at normal working pressure or head of the system. The gauge shall generally to comply with the relevant provisions of BS 1780 Part 2. 5.4.9 Pressure Relief Valve 1 The calorifier shall incorporate an enclosed spring loaded pattern pressure relief valve fitted with a padlock. The valve shall incorporate a copper discharge pipe running clear of any insulation and terminating 150 mm from floor level adjacent to a drain gully position. The pressure relief valve shall comply with the relevant provisions of BS 759. QCS 2010 Qatar Project Management 5.4.4 QCS 2010 Section 19 Part 5 Hot Water Storage Page 8 Combined Pressure and Vacuum Gauges 1 The calorifier shall incorporate a stainless steel dial type combined pressure and vacuum gauge. The dial shall be 100 mm diameter (minimum), white faced with a black figure scale, calibrated to suit steam chest pressure, complete with U pattern siphon and lever handle gauge cock. The gauge shall generally to comply with the relevant provisions of BS 1780 Part 2. 5.4.11 Vacuum Breaker 1 Vacuum breakers shall comply with the relevant provisions of BS 6282 Part 2 or 3. 2 Every vacuum breaker valve shall be of the same nominal size as the pipe on which it is connected. 3 Each vacuum breaker shall be installed at a height of not less than 150 mm above the overflowing level of the receiving cistern tank or appliance, when the later is fixed or not less than 300 mm above the outlet of the fitting in all other cases. 5.5 CISTERN TYPE WATER HEATERS 5.5.1 General Requirements 1 Cistern type water heaters shall comply with BS 417, BS 4213 and BS 4814, as appropriate. 2 The cistern shall comply with all the requirements for a cold water storage cistern. 3 The feed cisterns shall have a capacity at least equal to that of the hot water storage tank. 4 The feed cistern shall be situated at a height that will ensure a satisfactory flow of water at the highest point of discharge. 5.6 PRESSURE CONTROL 5.6.1 General Requirements 1 Whether hot or cold water is involved, it shall be ensured that no part of the system bursts due to the hydraulic pressures to which it is subjected. The pressures in the system shall never exceed the safe working pressures of the component parts. The maximum working pressure in a sealed primary circuit shall not exceed 3 bar but it shall be capable of passing a test at 1.5 times the working pressure at the working temperature. The maximum working pressure in an unvented hot water storage tank or secondary circuit shall not exceed 6 bar. 2 Where necessary the supply pressure shall be controlled by using break cisterns or by pressure reducing valves. If the supply to a storage type water heater is through a pressure reducing a valve of the type that permits backflow, the working pressure in the system shall be assumed to be the maximum pressure upstream of the valve. Where reliance is placed on pressure reducing valves to limit the maximum working pressure, these shall comply with BS 6283, Part 4. 3 Where unvented storage type water heaters are used, an expansion relief valve shall be fitted in the cold feed to the heater or hot water cylinder and no valves (other than a draining tap) shall be fitted between the expansion relief valve and the heater or hot water cylinder. 4 In every case, including sealed primary circuits, the expansion or pressure relief valve setting shall be maximum working pressure plus 0.5 bar to 1.5 bar. This also applies to combined temperature and pressure relief valves. QCS 2010 Qatar Project Management 5.4.10 QCS 2010 Section 19 Part 5 Hot Water Storage Page 9 VENTILATION 5.7.1 Storage Tanks 1 With ventilated hot water storage tanks, an open vent pipe shall run from the top of the hot water storage tank to a point above the cold water storage tank, into which it shall discharge. No valves shall be fitted to any vent pipe. The vent pipe shall rise continuously from its point of connection to the hot water storage tank to its point of discharge. The vent pipe shall be 19mm diameter or greater. 5.7.2 Indirect Calorifier Systems 1 Indirect calorifier systems incorporating vented primary circuits shall have vent route connecting the flow connection on the calorifier to the vent pipe above the expansion cistern and a feed water route from a point near the bottom of the expansion cistern to the return connection on the calorifier. These routes shall be independent. 5.8 EXPANSION VESSEL 5.8.1 General Requirements 1 An expansion vessel shall be connected to the cold feed supply pipe to unvented hot water storage vessels. There shall be no valve on the pipe between the expansion vessel and the storage vessel. 2 On indirect systems incorporating sealed primary circuits, an expansion vessel shall be connected to the section of pipework routing the water from the storage tank and boiler. 3 Provision shall be made to accommodate expansion water by one of the following alternative methods. (a) (b) (c) allow the expansion water to travel back along cold feed pipe, provided that heated water cannot reach any communication pipe or branch feeding a cold water outlet. where reverse flow along the cold feed is prevented by a stopvalve with a loose jumper, replace this valve by one with a fixed jumper. where reverse flow along the cold feed is prevented, e.g. by a check valve, some types of pressure reducing valve or a stopvalve with a loose jumper, provide an expansion vessel in accordance with BS 6144 to accommodate expansion water. This vessel shall be sized in accordance with the volume of water heated and the water temperature rise so as to limit the pressure to the maximum working pressure for the system. The expansion vessel shall accommodate expansion equal to 4% of the total volume of water heated. Any discharge from relief valves shall be readily visible and disposed of safely. 5.9 INSULATION 5.9.1 General 1 The storage tank shall be supplied complete with a factory applied layer of high density, CFC free polyurethane foam insulation. The dimensions and properties of the polyurethane insulation shall be sufficient to ensure that heat loss under normal operating conditions does not exceed 90 watts per square metre of surface area. 2 The polyurethane shall be protected against mechanical damage and moist atmosphere by an outer shell. END OF PART QCS 2010 Qatar Project Management 5.7 QCS 2010 Section 19 Part 6 Commissioning of Systems Page 1 6. COMMISSIONING OF SYSTEMS ................................................................. 2 6.1 GENERAL ...................................................................................................... 2 6.1.1 6.1.2 6.1.3 6.1.4 Scope System Description Submittals Connection to Water Supply System 6.2 PIPELINE IDENTIFICATION ......................................................................... 3 6.2.1 Tags and Colour Coding System 6.3 TESTING AND INSPECTION ........................................................................ 3 6.3.1 6.3.2 6.3.3 6.3.4 6.3.5 6.3.6 6.3.7 General Requirements Timing of Tests Inspection Leakage Test for Underground Pipelines Testing of Installation Within Buildings Back-Siphonage Mechanical and Electrical Equipment 6.4 DISINFECTION .............................................................................................. 5 6.4.1 6.4.2 6.4.3 General Requirements Installations Outside buildings Installation Inside Buildings 3 3 3 4 4 5 5 5 5 6 6 Qatar Project Management QCS 2010 2 2 2 2 QCS 2010 Section 19 Part 6 Commissioning of Systems Page 2 6. COMMISSIONING OF SYSTEMS 6.1 GENERAL 6.1.1 Scope 1 This Part specifies the requirements for identification markings for components of plumbing installations, testing of plumbing installations and disinfection of plumbing installations. 2 Related Sections and parts are as follows: Section 1 General Water Distribution Cold Water Storage Hot Water Storage General 6.1.2 System Description 1 Where possible and practicable, the parts of all Works covered in this Section shall be split into sections for interim testing purposes. Final testing shall be done when the installation is complete. 2 Disinfection shall not be undertaken until all tests and inspections have been completed to the satisfaction of the Engineer. 6.1.3 Submittals 1 The Contractor shall prepare a detailed testing and inspection programme, including method statements, and submit it to the Engineer for approval. This programme shall identify each item to be tested, the type of test to be performed and the date and time of the test. 2 The Contractor shall prepare test record sheets for all tests undertaken. The format of the test record sheet shall be to the approval of the Engineer. On successful completion of a test, the test record sheet shall be signed and stamped by all parties. The Engineer shall retain the original test record sheet. 3 The Contractor shall prepare a detailed disinfection programme, including method statements, and shall submit it to the Engineer for approval. This programme shall identify the date and time at which each item is to be disinfected. 4 The Contractor shall prepare disinfection record sheets for all disinfections undertaken. The format of the disinfection record sheet shall be to the approval of the Engineer. On completion of a disinfection, the disinfection record sheet shall be signed and stamped by all parties. The Engineer shall retain the original disinfection record sheet. 6.1.4 Connection to Water Supply System 1 Connection to the Qatar General Electricity & Water Corporation (QGEWC) water supply system shall not take place until all tests and inspections have been successfully completed and the system has been disinfected. 2 The Contractor shall comply with all the requirements of the QGEWC with respect to making the connection to the water supply system. QCS 2010 Qatar Project Management This Section Part 1 Part 2 Part 3 Part 5 QCS 2010 Section 19 Part 6 Commissioning of Systems Page 3 PIPELINE IDENTIFICATION 6.2.1 Tags and Colour Coding System 1 Marker tape shall be laid above all underground water mains. The marker tape shall be blue PVC or polyethylene mesh or ribbon at least 50 mm wide, incorporating a corrosion resistant tracing system. The tape shall be clearly marked “WATER” in both English and Arabic in black print. 2 Where aesthetically acceptable, above ground piping shall be clearly and indelibly marked “WATER” in both English and Arabic. Pipes solely for the use of fire fighting purposes shall be distinguishable from other water pipes. 3 Every valve in hot and cold water service pipework installed above ground shall be provided with an identification label. The label shall be secured by either non-corroding, incombustible means to the valve or fixed to a permanent structure near the valve. Labels secured to valves shall be of a non-corroding and incombustible material and clearly marked, by stamping or engraving, with a reference number for the valve. The reference numbers for the valves shall be as stated in the Project Documents. Labels fixed near valves shall comply with the requirements for labels secured to valves except that they need not be incombustible. 4 Surface boxes shall have “WATER” in both English and Arabic cast on. They shall be painted blue with a durable epoxy paint. 6.3 TESTING AND INSPECTION 6.3.1 General Requirements 1 The Contractor shall notify the Engineer at least two clear working days before hand of his intention to test any section of the Works. 2 Unless otherwise agreed by the Engineer, both interim and final tests shall be undertaken on each section of the Works. 3 The Contractor shall also carry out any further testing or inspections specifically requested by QGEWC. 4 Unless otherwise provided in the Project Documentation, the Contractor shall be responsible for providing all equipment and materials for testing purposes and for their removal and proper disposal on completion of testing. 6.3.2 Timing of Tests 1 The timing of tests shall be arranged as follows: (a) interim test shall be undertaken as soon as practicable after completion of a particular section; particular attention shall be made to work which will be concealed (b) final tests shall be carried out on completion of all work on items included in this Section and prior to handing over items failing any test shall be corrected immediately and re-tested before further work proceeds. (c) 2 The Contractor shall note that satisfactory completion at an interim test does not constitute a final test. QCS 2010 Qatar Project Management 6.2 QCS 2010 Section 19 Part 6 Commissioning of Systems Page 4 6.3.3 Inspection 1 Visual inspection shall be carried out at both interim and final testing in order to detect faults in construction or materials not shown up under testing but which could lead to premature failure. A careful record shall be kept of such inspections. 2 On external pipelines, the following shall be visually inspected: pipe bed pipe line and level joints air valves washout valves gate valves thrust blocks pipe protective coating any other pipeline appurtenance. 3 Trenches shall be inspected to ensure that excavation is to the correct depth to guard against mechanical damage due to traffic loading. 4 No part of the pipe trench shall be backfilled until the above are satisfactory completed and approved by the Engineer. 5 All internal pipework shall be inspected to ensure that it has been securely fixed. 6 Before testing takes place, all cisterns, tanks, hot water cylinders and water heaters shall be inspected to ensure that they are properly supported and secured, that they are clean and that cisterns are provided with correctly fitting covers. 7 Before testing takes place, all electrical and mechanical items shall be inspected in accordance with Section 9, Mechanical and Electrical Equipment. 6.3.4 Leakage Test for Underground Pipelines 1 After satisfactory visual inspections have been completed, hydraulic pressure testing shall be carried out on the installation. The testing procedure shall be as follows: (a) (b) (c) (d) gauges used for testing pressure pipelines shall either be of the conventional circular type, not less than 200 mm diameter, calibrated in metres head of water, or shall have a digital indicator capable of reading increments of 0.1m head. Before any gauge is used, the Contractor shall arrange for it to be checked independently and a dated certificate of its accuracy shall be provided before testing, valves shall be checked and sealed, the sections of pipe filled with water and the air released. After having been filled, pipelines shall be left under operating pressure for the period described in the Project Documentation or as directed by the Engineer, so as to achieve conditions as stable as possible for testing the pressure in the pipeline shall then be raised steadily by pumping in water until the specified test pressure, as given in the Project Documentation or as directed by the Engineer, is reached in the lowest part of the section. The pressure shall be maintained at this level, by pumping if necessary, for a period of one hour. The pumps shall then be disconnected, and no further water shall be permitted to enter the pipeline for a further period of one hour. After the one hour test period, the pressure in the pipe shall be recorded. At the end of this period the original test pressure shall be restored by pumping in water and the loss measured by drawing off water form the pipeline until the pressure as recorded at the end of the one hour test period is again reached the permissible loss shall not exceed 2 litres per metre nominal bore per kilometre length per metre head (calculated as the average head applied to the section) per 24 hours. This relationship in equation format, with the leakage measured in litres, can be written as follows: QCS 2010 Qatar Project Management (a) (b) (c) (d) (e) (f) (g) (h) (i) QCS 2010 Section 19 Part 6 Commissioning of Systems Page 5 Permissible leakage per day = 2 x D x P x L For the one hour test period, this equation can be rewritten as follows: Permissible leakage = (2 x D x P x L) / 24 Where: D = pipe diameter (m) P = test pressure (m) L = length of test section (km) (e) 2 To avoid the risk of contamination, water used for testing shall be obtained from a potable supply. 3 Before accepting a pipeline, a check shall be made that valve boxes are properly aligned, that suitable operating keys are provided which can be easily fitted to the valves and in the case of deep valves, that adequate extension spindles are installed. 6.3.5 Testing of Installation Within Buildings 1 When the installation is complete and visual inspection has been satisfactorily completed, it shall be slowly filled with water, with the highest draw-off point open to allow air to be expelled from the system. The installation, including all cisterns, tanks cylinders and water heaters, shall then be inspected for leaks. 2 The system shall be hydraulically tested in the following way: (a) (b) subject the pipes, pipe fittings and connected appliances to a test pressure at least 1.5 times the maximum working pressure for a period of at least 24 hours check the installation for leaks; including all cisterns, tanks, cylinders and water heaters. 3 Each draw-off tap, shower fitting and float-operated valve shall be checked for flow against specified requirements. Performance tests shall also be carried out on any specialist items to show that they meet the requirements detailed in the Project Documentation. 6.3.6 Back-Siphonage 1 It shall be verified that the appropriate back-flow prevention devices have been selected and that they have been installed correctly. 6.3.7 Mechanical and Electrical Equipment 1 Mechanical and electrical equipment shall be tested and commissioned in accordance with Section 9, Mechanical and Electrical Equipment. 6.4 DISINFECTION 6.4.1 General Requirements 1 All hot water systems and cold water systems installed shall be disinfected before being taken into use. QCS 2010 Qatar Project Management (f) in addition to the tests on separate sections, the whole pipeline shall be tested on completion to the same pressure and by the same procedures as that outlined for individual sections where a new pipeline is to connect to an operational pipeline the final connection shall be inspected visually under normal operating pressure and there shall be no visible leakage. QCS 2010 Section 19 Part 6 Commissioning of Systems Page 6 Where chlorinated water that has been used to disinfect an installation is to be discharged into a sewer, the Drainage Department shall be informed. 3 Unless otherwise stated in the Project Documentation, the Contractor is responsible for providing water for disinfection purposes. 6.4.2 Installations Outside buildings 1 At the time of laying, large bore pipes shall be brushed clean and sprayed internally with a strong solution of sodium hypochlorite. 2 At the time of laying, small bore pipes shall be swabbed with a polyurethane foam plug soaked in a strong solution of sodium hypochlorite. A water jet may be used to push the plug along the pipe. 3 Following the disinfection process, the pipe shall be regarded as operational and the Contractor shall not open or close any valves or take any other action which might interfere with the use of the pipe. 6.4.3 Installation Inside Buildings 1 All visible dirt and debris shall be removed from the cistern. 2 The cistern and distributing pipework shall be filled with clean water and then drained until empty of all water. The cistern shall be filled again and the supply closed. 3 A measured quantity of sodium hypochlorite solution of known strength shall be added to the water in the cistern to give a free residual chlorine concentration of 50 mg/litre in the water. 4 The cistern shall be left to stand for 1 hour. Then each draw-off fitting shall be successively opened working progressively away from the cistern. Each tap or draw-off fitting shall be closed when the water discharged begins to smell of chlorine. The cistern shall not be allowed to become empty during the operation; if necessary it shall be refilled and chlorinated as detailed above. Should refilling be necessary, the cistern and pipes shall be left for a further hour before continuing the disinfection procedure. 5 The tap furthest from the cistern shall be opened and the level of free residual chlorine in the water discharged from the tap shall be measured. If the concentration of free residual chlorine is less than 30 mg/l the disinfecting process shall be repeated. 6 Finally, the cistern and pipes shall remain charged with chlorinated water for at least 16 hours and then thoroughly flushed out with clean water until the chlorine concentration at the taps is no greater than that present in the clean water from the QGEWC supply main. 7 For installation with more than one cistern, all cisterns shall be cleaned and chlorinated, in accordance with paragraph 1 to 4 above, simultaneously. END OF PART QCS 2010 Qatar Project Management 2 QCS 2010 Section 19 Part 7 Plumbing For Gases Page 1 7. PLUMBING FOR GASES .............................................................................. 2 7.1 GENERAL ...................................................................................................... 2 7.1.1 7.1.2 7.1.3 7.1.4 Scope References Compliance Quality Assurance 7.2 MATERIALS................................................................................................... 3 7.2.1 7.2.2 Gas System Accessories Compressed Air System Accessories 7.3 EXECUTION .................................................................................................. 4 7.3.1 7.3.2 Hangers and Supports Execution Requirements 3 3 4 4 Qatar Project Management QCS 2010 2 2 2 2 QCS 2010 Section 19 Part 7 Plumbing For Gases Page 2 7. PLUMBING FOR GASES 7.1 GENERAL 7.1.1 Scope 1 The work covered in this Part consists of providing all plant, labour and materials and performing all operations in connection with gas and compressed air supply in buildings. 7.1.2 References 1 The following standards are referred to in this Part: Building Services Piping Health Care Facilities 7.1.3 Compliance 1 Installation and testing of gas system shall be in accordance with NFPA 99. 2 Gas pressure vessels and relief valves shall be in accordance with the relevant ASME codes. 3 Fabrication and installation of gas systems shall be in accordance ASME B 31.9. 4 Electrical components for compressed air systems shall be listed and labelled by Underwritten Laboratories. 7.1.4 Quality Assurance 1 Manufacturers of gas and compressed air system products shall have been regularly engaged in the manufacture of such products, of the type and size specified in the Project Documentation, that have been in satisfactory use in similar service conditions for not less than five years. 2 Installation of gas and compressed air system shall be carried out by specialists with at least three years of successful installation experience of gas and compressed air systems similar to the type specified in the Project Documentation. 3 Upon completion and prior to acceptance of the installation, the contractor shall carry out operating and pressure tests at not less than 1.5 times the operating pressure, checked at half hour intervals to demonstrate satisfactory functional and operational efficiency. Such operating tests shall take place over a continuous period of not less than 8 hours for each system and shall include the following information in a report with a conclusion as to the adequacy of the system: (a) (b) (c) a description of the test method including references to standard testing procedures if appropriate time, date and duration of the test compressed air pressure readings of the compressor at each outlet. QCS 2010 Qatar Project Management ASME B 31.9 NFPA 99 QCS 2010 Section 19 Part 7 Plumbing For Gases Page 3 MATERIALS 7.2.1 Gas System Accessories 1 Gas cocks shall be bronze with a square head and shall have distinctly marked ON-OFF indications. They shall be pressure rated for 900 kPa (9.0 bar). The units shall conform with SSA 119 and shall be provided with an identification label. Labels shall be visible after installation. Where quick-type couplers are furnished, they shall be of the noninterchangeable type. The connector shall lock firmly into position and shall have a fingertype quick release. 2 A wrench shall be provided and attached to each cock. 3 Pressure regulators shall be in accordance with SSA 121 and shall have an adjustable diaphragm actuated by a spring-loaded pressure reducing valve, designed for liquid petroleum gas (LPG) systems. Pressure regulators shall be provided with a relief valve, and the diaphragm chamber shall be piped to the outside of the building. Pressure regulators shall be approved and marked by authorised officials recognised by a Qatari authority. 4 Shut-off valves shall be wafer type ball valves with bronze body, ball and stem, non-stick seats, seals, O-ring packing and lever handle. Shut-off valves shall have socket ends or threaded socket adapters. 5 Check valves shall be of the threaded bronze spring type with composition disc and bronze spring or of the silent double-centre guided conical spring type. 6 Safety relief valves shall have a spring-loaded shuttle with a pressure adjustment corresponding to the highest permissible working pressure of the cylinder. 7 Pipe failure valves shall have a spring-loaded shuttle suitable to shut off the flow of the gas if the rate of flow is too high. 8 Pressure gauges shall be a black enamel cast iron or cast aluminium case, chromium plated brass ring with a heavy glass, phosphor bronze bushed rotary precision movement, and a dial with a suitable pressure range. 7.2.2 Compressed Air System Accessories 1 Air compressors shall be of the reciprocating air cooled type. 2 Compressors shall consist of replaceable finned cast iron cylinders, flanged cast iron or cast aluminium heads, cast iron or cast aluminium pistons with rings made of carbon or non-stick and forged steel, bronze or aluminium connecting rods. Crank cases shall be made of cast iron. Each compressor shall have an automatic unloader system for no-load start up, a positive pressure lubricating system and stainless steel strip valves 3 Compressors and motors shall be direct-connected or operated by means of a V-belt drive, and provided with guard for flywheel and belts. 4 Motors shall be of the single-phase type or the three-phase type. Motors shall be standard open frame, drip proof, ball bearing 40ºC rise NEMA standard design “B” induction type. Single-phase motors shall have grease lubricated ball bearings and built-in overload. Threephase motors shall have rigid base mounting with slide rails for belt adjustment. Motor voltage shall be as given in the Project Specification. 5 Air receivers shall be suitable for the specified system working pressure, designed and constructed in accordance with the relevant ISO Standards. QCS 2010 Qatar Project Management 7.2 QCS 2010 Section 19 Part 7 Plumbing For Gases Page 4 Air receivers shall be provided with condensate drain trap, relief valve, pressure gauge, and welded steel supporting feet. 7 The outside of air receivers shall either be galvanised or supplied with a commercial enamel finish. 8 Air dryer units shall be of the package assembled type with a cabinet enclosing refrigeration unit, hot bye-pass valve, heat exchanger, moisture separator, chiller section with replaceable type cartridge filter, temperature and pressure gauges, controls and condensate drain trap. 9 Refrigeration units shall be of the hermetically sealed compressor type with air cooled condenser. 10 The cabinets shall be made of steel and finished with commercial enamel, and provided with top-hinged access door and front panel for easy access. 11 Control valves shall be of the top entry or wafer type ball valve with bronze body, ball and stem, non-stick seats, and lever handles with socket ends or threaded socket adapters. 12 Check valves shall be of the threaded bronze spring type with composition disc and bronze spring or of the silent double-centre guided conical spring type. 13 Pressure regulating valves shall be of the adjustable, direct-acting, single-seat, springactuated diaphragm type, or of the double-seated valve plug type, the body shall be made of cast iron, die cast zinc or bronze. 14 The regulator shall be provided with an adjustment device for adjusting pressure differential, and shall be of the same size as the pipe. 15 The filter regulator units shall consist of a bronze or die cast zinc body, actuated by an adjustable direct-acting single-seat spring diaphragm type regulator. 16 The filter regulator units shall be provided with filter units, suitable to filter the supply air of particles down to fine micron size, and pressure gauges. 17 Pressure gauges shall have a black enamel cast iron or cast aluminium case, a chromium plated brass ring with a heavy duty glass cover, a phosphor bronze bushed rotary precision movement, and a dial with a suitable pressure range. 18 Drains shall be the brass pre-cock type in low points of the compressed air system, or the automatic drain type. 7.3 EXECUTION 7.3.1 Hangers and Supports 1 Hangers in contact with copper tubing shall be electrolytically coated and shall be sized to suit the outside diameter of the pipe. 7.3.2 Execution Requirements 1 For gas systems only copper tubing shall be used. Joints shall be made either by soldering or welding. Jointing material shall be suitable for soldering and welding gas pipes. 2 No gas piping shall be installed under any building or structure and all exposed gas piping shall be kept at least 150 mm above the ground. QCS 2010 Qatar Project Management 6 QCS 2010 Section 19 Part 7 Plumbing For Gases Page 5 When stand-by gas is connected to the gas piping system, an approved three-way, two-part valve or other adequate safeguard shall be installed to prevent backflow into either supply system. 4 An accessible shut-off valve shall be installed in the gas piping system near each appliance and the head of the union connection thereto, and in addition to any valve on the appliance. Shut-off valves shall be within 1.0 m of the appliance. Shut-off valves may be located immediately adjacent to and inside or under an appliance when placed in an accessible and protected location and when such appliance may be removed without removal of the valve. 5 Appliance connections shall, at no time, have a diameter less than that of the inlet connection to the appliance as provided by the manufacturer. 6 Compressed air piping shall be copper steel, installed free of traps and graded to low points with condensate drain pet-cocks, or automatic condensate drain traps, as required in the Project Specification or shown on the Project Drawings. 7 Compressors shall start unloaded and shall start and stop automatically by means of an enclosed diaphragm-type pressure switch mounted on the unit. 8 Guards shall be provided for all exposed moving parts. 9 After cooler and moisture separator shall be installed between the compressor and the air receiver to remove moisture and oil condensate before the air enters the receiver, except where air dryers are installed. 10 Vacuum cleaning piping shall be made of plastic or steel and shall slope to the separator free of traps. Changes in the direction of piping shall be made by using 45 degree bends or long turn tees or bends, and shall be slip jointed. 11 Drop lines shall be connected from side or top of horizontal lines only. 12 Cleanout plugs shall be provided at all changes in direction and/or as indicated in the Project Specification or shown on the Project Drawings. 13 Floor mounted vacuum inlet valves shall be flush with floor finish. 14 The vacuum producer unit shall be provided with rubber inlet sleeve and stainless steel clamps for connecting unit to piping. END OF PART QCS 2010 Qatar Project Management 3