BATHROOMS 6 by Bill Allan SECTION 601 REVISITED The IEE’s technical helpline continues to receive regular questions about Section 601 – locations containing a bath or shower – and Part P contains requirements for such locations. Most callers are now familiar with the concept of zones with specified degrees of protection against ingress of moisture for equipment. Readers may wish to review the article, ‘Section 601 – Flushing out the Facts’ in Issue 8 (Autumn 2000) of Wiring Matters. This article has been written in response to some of the questions recently received. IEE Wiring Matters | Autumn 2004 | www.iee.org BATHROOMS 7 ELECTRICAL EQUIPMENT The term ‘fixed current-using equipment’ is used a number of times in Section 601 and some are unclear as to what is meant by it. Before answering, permit me to ask a further couple of questions. What is meant by the expression in Regulation 601-09-03, ‘current-using equipment other than fixed current-using equipment’? (It may be helpful to call this type of equipment nonfixed current-using equipment). Further, the term ‘current-using equipment’ implies that there is also non-current-using equipment. In summarising these terms, we should be aware that the term ‘Electrical equipment’ is defined in Part 2 of BS 7671 and includes accessories, appliances and luminaires. 1. Fixed current-using equipment Current-using equipment is equipment which consumes current rather than simply transmitting or switching current. This would include luminaires and fans, for example. 2. Fixed non current-using equipment This includes switches and fused connection units. 3. Non-fixed current-using equipment The expression ‘current-using equipment other than fixed current-using equipment’ used in Regulation 60109-03 (or non-fixed current-using equipment) refers to items of stationary equipment. Stationary equipment is defined as equipment having a mass exceeding 18kg and not provided with a carrying handle. This would include such items as washing machines and tumble dryers. Before anyone asks, we’ll assume that, in the context of Section 601, there is no such thing as non-fixed non current-using equipment! equipment when it is permanently connected to the supply via a fused connection unit? The answer is generally no, but a problem arises with hand-held equipment. The situation with hair dryers illustrates the point. It is generally recommended that the pistol grip type of hair dryer should be avoided within the zones, but the flexible hose type can be connected within zone 3 when supplied from a fused connection unit protected by a 30mA RCD. BEYOND ZONE 3 For the larger bathroom and shower room with space beyond zone 3, portable equipment is not excluded by Section 601. This means that hair dryers may be installed – even the pistol grip variety – but, while Section 601 does not require them to be protected by a 30 mA RCD, it may be advisable to supply them using a fused connection unit protected by a 30mA RCD. SHAVER SUPPLY UNITS The minimum degree of protection for equipment installed in zones 1 and 2 is IP4X or IP5X where water jets are likely to be used for cleaning purposes in communal baths or communal showers. An exception to this requirement is a shaver supply unit complying with BS EN 60742 Chapter 2, Section 1, which, although it does not meet the requirements of IP4X, is permitted in zone 2 but must be located where direct spray from showers is unlikely. This type of shaver supply unit, which incorporates a safety isolating transformer, is the only type which is permitted in a bathroom or shower room. However, where a shower cubicle is installed in a room other than a bathroom or shower room, e.g. in a bedroom, this particular type of shaver supply unit is not insisted upon. (See Regulation 601-08-02) WHAT IS PERMITTED IN ZONE 3 There are no particular ingress protection requirements for zone 3. This means that BS 1363 accessories, such as switches and fused connection units, can be installed in zone 3, subject to the requirements of Regulation 512-06-01. Non-fixed current-using equipment, such as washing machines and tumble dryers for example, may be installed in zone 3, subject to manufacturers’ approval. Such equipment must be supplied by means of a fused connection unit and be protected by a 30mA RCD. HAIR DRYERS Portable equipment is not permitted in zone 3, other than that associated with SELV socket outlets and shaver supply units. However, the question arises: is an item of portable equipment still an item of portable IEE Wiring Matters | Autumn 2004 | www.iee.org BATHROOMS 8 RCDS Residual current devices (RCDs) having a rated residual operating current I=n not exceeding 30mA are required in the following situations: ■ the supply circuit of fixed current-using equipment (other than water heaters or shower pumps) which can reasonably only be located in zone 1; ■ the supply circuit of current-using equipment other than fixed current-using equipment in zone 3; ■ The circuit supplying 230V BS 1363 socket outlets in a room other than a bathroom or shower room. (It should be noted that the zonal protection system applies to such rooms and the socket outlets must be located outside the zones). Section 601 does not require RCDs in circuits supplying electric showers. ‘IN A ROOM OTHER THAN A BATHROOM OR SHOWER ROOM’ Regulation 601-08-02 permits the installation of 230V BS 1363 socket outlets ‘Where a shower cubicle is installed in a room other than a bathroom or shower room’. Such socket outlets must be installed outside zones 0, 1, 2 or 3 and be protected by a 30mA RCD. However, no such relaxation is made for baths located in rooms other than bathrooms. It is not uncommon these days to have a bath installed in a bedroom or even in a lounge. Such a room effectively becomes a bathroom and is subject to the requirements of Section 601. For example, 230V BS 1363 socket outlets would not be permitted. SUPPLEMENTARY EQUIPOTENTIAL BONDING Local supplementary equipotential bonding, complying with Regulation 547-03, is required between the terminals of circuits supplying Class 1 and Class 2 equipment in Zones 1, 2 and 3 and all extraneous-conductive-parts in these zones. USING CPCS AND EXTRANEOUS-CONDUCTIVE-PARTS AS SUPPLEMENTARY BONDING CONDUCTORS Circuit protective conductors (CPCs), such as that between a luminaire and its switch, for example, may be utilised as a bonding conductor. Therefore the supplementary bonding conductor may be connected either at the switch or at the luminaire. Similarly with shower circuits, the supplementary bonding conductor may be connected either at the shower switch or at the shower itself. Regulation 543-02-02 (vii) permits extraneousconductive-parts, where they comply with Regulation 54302-06, to be used as supplementary bonding conductors. WHERE IT IS NOT NECESSARY TO SUPPLEMENTARY BOND It is not necessary to supplementary bond items of metalwork which are supplied by plastic pipes, as such metalwork is unlikely to come within the definition of an extraneous-conductive-part. Neither is it necessary to supplementary bond short lengths of copper pipes which are sometimes installed for aesthetic reasons in an otherwise plastic system. In a room other than a bathroom or shower room, supplementary bonding is not required in zone 3. WHERE SUPPLEMENTARY BONDING IS CARRIED OUT Supplementary bonding does not have to be carried out within the bathroom or shower room itself, it can be provided at a convenient location in close proximity. This may be in an adjacent airing cupboard, or within the ceiling space or under the floor boards. CONCLUSION No doubt there are other questions which could be dealt with regarding Section 601, but they will have to wait until another time. ■ Published by IEE Publishing & Information Services Michael Faraday House, Six Hills Way, Stevenage, Herts, SG1 2AY, United Kingdom Tel: +44 (0)1438 313311 Fax: +44 (0)1438 313465 Sales and Project Coordinator K Hunton Tel: +44 (0)1438 767224 Email: khunton@iee.org.uk | Editor: G D Cronshaw Tel: +44 (0)1438 767384 Email: gcronshaw@iee.org.uk | Contributing Editors: P R L Cook, P E Donnachie, W R Allan IEE Wiring Matters is a quarterly publication from the Institution of Electrical Engineers (IEE). The IEE is not as a body responsible for the opinions expressed. ©2004: The Institution of Electrical Engineers. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means without the permission in writing of the publisher. 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Web-offset printing by Wyndeham Heron, The Bentall Complex, Colchester Road, Heybridge, Maldon, Essex, UK Co-operating Organisations The Institution of Electrical Engineers acknowledges the contribution made by the following organisations in the preparation of this publication. | British Electrotechnical & Allied Manufacturers Association Ltd – R Lewington, P D Galbraith, M H Mullins | Office of the Deputy Prime Minister – K Bromley, I Drummond | Electrical Contractors Association – D Locke, S Burchell | City & Guilds of London Institute – H R Lovegrove | Energy Networks Association –D J Start | Electrical Contractors Association of Scotland t/a | SELECT – D Millar, N McGuiness | Health & Safety Executive – N Gove | National Inspection Council for Electrical Installation Contracting IEE Wiring Matters | Autumn 2004 | www.iee.org