CHEMICAL HANDLING Postgraduate Induction Safety Training S Burrows P230 [email protected] General remarks • safe preparation of samples • safe handling of samples provided from elsewhere • safe handling of chemicals NB specific training – HF handling http://www2.warwick.ac.uk/fac/sci/physics/intranet/healthsafety/hydro/ http://www.hse.gov.uk/pubns/indg307.htm http://www.nanolab.ucla.edu/pdf/HF_First_Aid.pdf Chemical Hazards Information on hazards: The COSHH (Control of Substances Hazardous to Health) sheet (US – MSDS) Should be consulted for every chemical substance which you use NB – it does not cover all possibilities of combination with other chemicals, heat and pressure Flammable Hazards oxidising atmosphere + flammable vapour + source of ignition. Flash Point. Lowest T at which vapour pressure above liquid is sufficient to form an ignitable mixture with air near the surface of the liquid. e.g. acetone (-18° C) or diethyl ether (-45° C). (Auto-) Ignition Temperature Minimum T required to initiate self-sustained combustion. Does not require source of ignition. e.g. diethyl ether (160° C) Pyrophoric materials Auto-ignites usually by exothermic reaction with oxygen or water – e.g. fine metal powders Reactive Hazards Oxidising Agents - combustion Explosives Peroxides - explode Reactive mixtures hazardous product Corrosive Hazards • destroy tissue (internal and external) • e.g. strong acids and bases, dehydrating agents, halogens; compounds that hydrolyse to acids (e.g. phosphates) or bases (e.g. caesium salts). Chemicals Harmful to Health other than Reactive, Corrosive or Flammable. • range of toxic attributes and responses, some of which are not immediately obvious (e.g.carcinogen; sensitisation) • ingestion, inhalation, absorption • extent of exposure important – amount - LD50 7000mg/kg of body weight for ethanol 0.02mg/kg for dioxins. time/frequency Ordering Hazardous Chemicals Sample preparation Sources of information on hazards • • • • COSHH or MSDS sheet literature (preferably more than one source!) supervisor safety advisors MSDS sheets are often available from chemical companies e.g. Sigma-Aldrich No information! If you cannot find information on the procedure which you wish to carry out: • Risk assessment • appropriate precautions to minimise risk Some precautions • • • • Fume cupboard (available in certain labs) gloves (correct type) safety glasses face mask (correct type) Any procedures which cannot be safely dealt with using the safety equipment above are likely to require special facilities and cannot be carried out in Physics SAMPLE LABELLING REASONS 1. 2. 3. SAFETY – we MUST be able to assess the hazards associated with samples which are in use or stored in the laboratories. FUTURE – we NEED to be able to identify samples exactly if measurements are to be made in future when “owner” may have left. DISPOSAL – we MUST be able to tell disposal contractors what chemicals are present in any samples which are for disposal. SAMPLE LABELLING LABELS • must include chemical components e.g. Na2O-B2O3-SiO2 • (full composition even better) e.g. 20Na2O-20B2O3-60SiO2 THIS IS MANDATORY SAMPLE LABELLING - further information on processing/testing e.g. 1200oC/2h; ND; 29Si NMR “owner” e.g. A. Surname relevant date of manufacture/test e.g. 12/08/13 Labels must be difficult to detach from the sample container. SAMPLE LABELLING SAMPLE CONTAINERS These must be suitable for the sample state and the containment conditions. For example – plastic self-seal bags do not survive well in vacuum desiccators and push-fit caps come off sample tubes! SAMPLE STORAGE Hazardous samples must not be handled in offices (and remember that many materials are harmful in powder form). Samples in containers may be stored in offices if they are inaccessible to others – e.g. in locked drawer. Sample storage facilities should be available within your group area CHEMICAL STORAGE There should be designated separate storage areas for general laboratory chemicals such as solvents, acids, bases. Usually an integral part of fume cupboard structure or metal bins. SAMPLES IN USE Material being processed or samples being characterised must have a warning notice nearby giving the labelling information above + any hazard data. YOU ARE RESPONSIBLE FOR THE SAFETY OF THE PEOPLE AROUND YOU AS WELL AS YOUR OWN CLEAN UP AFTER YOU!!!! DISPOSAL OF WASTE CHEMICALS (non-radioactive) The following procedure should be adopted when disposing of waste chemicals: Complete a Chemical Disposal Form (obtainable from stores or the departmental web-site). Package and label the waste. Information must include all chemical constituents of the waste (with proportions if known); the originator of the waste; and the date of disposal. Give the waste + form to Alan Burton who will enter the information into the disposal log and put the waste into store ready for collection. CHEMICAL DISPOSAL FORM Complete form and give copy, with material for disposal, to ?????. SAMPLE LABEL CHEMICAL CONSTITUENTS FULL CHEMICAL COMPOSITION (if known) STATE (liquid/solution/powder/ lumps etc) SPECIFIC HAZARD if known (flammable/toxic etc) ORIGINATOR GROUP DATE CHEMICAL DISPOSAL FORM Complete form and give copy, with material for disposal, to ??????. SAMPLE LABEL Antimony silicate glass Sb60Si40 03/07/05 CHEMICAL CONSTITUENTS Sb2O3, SiO2, Fe2O3 FULL CHEMICAL COMPOSITION (if known) 60 mol% Sb2O3 40 mol% SiO2 0.1 mol% Fe2O3 STATE (liquid/solution/powder/ lumps etc) POWDER AND FRAGMENTS SPECIFIC HAZARD if known (flammable/toxic etc) TOXIC (Sb) AND DUST ORIGINATOR A.N.OTHER GROUP R101 DATE 06/06/13 WASTE CONTRACTOR’S FORM Waste Details: Description of waste (EWC Code) Containers Chemical/ biological components of waste and %ages Physical Form Number Size Units Type List of Wates PHSDRID Comment & Criteria DISPOSAL OF WASTE CHEMICALS (non-radioactive) Solvents: where these are used regularly in small amounts, the resulting waste can be accumulated in an appropriate labelled container (separate for each solvent) prior to disposal. DISPOSAL OF WASTE CHEMICALS (non-radioactive) Some water soluble/miscible chemicals can be disposed of to the drains but advice should be sought on this from supervisor or department safety officer. DISPOSAL OF WASTE CHEMICALS (non-radioactive) Disposal of waste whose chemical composition is unknown is extremely expensive and therefore it is important that you keep complete and accurate records and that your samples are labelled with sufficient detail that their composition is clear.