Biological Monitoring For Isocyanates

Transcription

1 Biological Moitorig For Isocyaates Employers Guidace for Employers ad Occupatioal Health Providers o the aalysis of workers urie to assess exposure to isocyaates The Health ad Safety Laboratory is a Agecy of the Health ad Safety Executive

2 Biological Moitorig For Isocyaates Urie aalysis for isocyaates Part 1 What is the problem with isocyaates? Isocyaates occur i may 2-pack (2K) paits ad other products. Breathig i isocyaate is the top cause of work-related asthma i Britai. Ayoe gettig asthma from isocyaates will be uable to work with them agai. As a employer, you have a duty to cotrol adequately your workers exposure to isocyaate 1. For example, you may be providig vetilated spray booths, air-fed breathig apparatus ad extracted gu cleaers. But how ca you prove that your employees are safe, particularly as sprayers are egulfed by ivisible mist whe sprayig ad you are relyig o correct behaviour as well as equipmet maiteace to prevet exposure? Your idustry has agreed that the best ad simplest way to do this is by aalysig your worker s urie for traces of isocyaates (biological moitorig 2 ). If you use isocyaate-based products, you ormally eed a health surveillace scheme 3. We recommed your surveillace scheme provider helps you with biological moitorig. There is a biological moitorig guidace value for isocyaate traces i urie. The value is 1 micro mol uriary di-amie per mol creatiie for a urie sample collected at the ed of the task. Most compaies usig good cotrol ca get below 1. Why aalyse urie? The body breaks dow ay isocyaates that are breathed i ad quickly elimiates them (as di-amies) i urie. The more isocyaate is breathed i, the more di-amie there is i urie. If cotrols are workig correctly e.g. the breathig apparatus is workig ad used properly the workers will ot breath i ay isocyaate ad we will ot fid ay di-amies i urie. Who eeds moitorig? You should moitor all workers who may breathe i isocyaates. I MVR bodyshops this ormally meas the sprayers. Is it compulsory? Employees may refuse to give a sample. Hopefully, if you explai why the sample is required ad assure them that othig else is checked for, their cocers will be addressed. Nevertheless, legally, they must cooperate with you so that you ca fulfil your health ad safety duties 4. If your COSHH risk assessmet idicates that moitorig of exposure is ecessary to esure your cotrols measures are workig (ad for sprayig isocyaates i a spraybooth/room it should) the you have a legal duty to moitor (uless you ca demostrate compliace by some other method of evaluatio). We are ot aware of ay other procedure that ca demostrate this compliace. Cosequetly, moitorig requires their cooperatio. The guidace value is about exposure cotrol: it has o direct meaig for health.

3 Biological Moitorig For Isocyaates How? Part 2 If, after explaiig all of this to the employee, they still refuse to cooperate you will eed to decide whether you are prepared to place yourself i breach of the Regulatios or take further actio. You may wish to discuss this with your local HSE ispector. Ultimately, you may decide to move the employee to positio where they are o loger potetially exposed to isocyaates. Iformed coset It is importat that your workers uderstad what is beig doe ad why, so they ca give iformed coset. We recommed your health surveillace scheme provider helps you with biological moitorig You eed to explai to workers that you are checkig the cotrols to prevet exposure to isocyaates that could give them asthma. This will ormally be doe oce a year, uless the results show there is a problem. Ask them to provided a urie sample at the ed of a typical spray sessio usig isocyaate products Tell them that oly thigs related to isocyaates ( biomarkers ) will be measured i the sample - ot drugs, alcohol etc. (they have ot give permissio ad you are ot payig for it) Ask them if they will let you see their results because if there is a problem you will eed to work together to sort out ay problems. Tell them that the results will ot say aythig about their health or risk of ill-health, oly their exposure. Tell them that if the results show cotrols are ot workig properly, you will both eed to fid out why, sort it, ad the have a further urie sample measured. How to collect samples We provide 30ml plastic bottles cotaiig a little white preservative. The worker should direct a sample of urie ito the bottle at the ed of a work sessio, ad close the bottle firmly. Nobody wats leaks! Label the bottle with the worker s ame ad the date. Complete the sample request form, ad tell us where to sed the results. Put the bottle ad form i our packagig. Sed it to us by first class post. Will aythig else be measured? No. The laboratory will oly aalyse the sample for isocyaate breakdow products ad creatiie to check the sample is urie (ad ot water) ad to adjust the result for a weak or strog sample. The laboratory will ot aalyse the sample for drugs, alcohol, pregacy, HIV or aythig else. How ofte should we moitor? It depeds. Take several samples, util you are cofidet about your cotrols. With results that fall at or below the guidace value, sample oce a year uless work practices chage or you employ ew workers. With results that are above the guidace value, ivestigate, make chages ad take more samples. Sample util you have cofidece i the cotrol measures.

4 Biological Moitorig For Isocyaates Results Part 3 The laboratory will report your results somethig like this: Name 2,4 Tolueediamie µmol/mol creatiie 2,6 Tolueediamie µmol/mol creatiie 1,6 hexaediamie µmol/mol creatiie IPDA µmol/mol creatiie MDA µmol/mol creatiie Mr Smith ND ND ND ND ND Mrs Joes ND ND 0.5 ND ND Mr Smart ND ND 2 ND ND UK Guidace Value The colums show the breakdow products of differet types of isocyaates: 2,4 tolueediisocyaate (TDI) breaks dow to 2,4 tolueediamie 2,6 tolueediisocyaate (TDI) breaks dow to 2,6 tolueediamie hexamethyleediisocyaate (HDI) breaks dow to 1,6 hexamethylediamie isophoroediisocyaate (IPDI) breaks dow to IPDA(u) (isophoroediamie) methyleedipheyl diisocyaate (MDI) breaks dow to MDA (methyleediailie) The levels of the diamies are reported as µmol/mol creatiie (micro mol/mol creatiie). Creatiie is foud i everyoe s urie ad is used to adjust the level of diamies to compesate for dilute or cocetrated urie. Importat: If the results are ND (like Mr Smith above), or are at, or below, the guidace value of 1 micromol uriary diamie per mol creatiie (like Mr Joes above), your cotrols i place o the day of the sample are adequate. Keep a eye o the cotrols, ad your workers use of breathig apparatus. Sed ew samples i a year's time. If somethig chages, or you have ew workers sed i samples before the aual check. A result above 1 does ot mea you will get asthma. It meas that cotrols are ot workig properly.

5 Biological Moitorig For Isocyaates Results Part 3 If the results are above the guidace value of 1 (like Mr Smart above), your cotrols may be iadequate or else ot used properly. Check that everythig is workig. Cosider: Carryig out a ew clearace time test with smoke, which will also reveal if the booth/room is leakig Is the air-lie breathig apparatus beig maitaied ad are workers usig it properly? Has the breathig air quality ad quatity bee tested recetly? Are sprayers liftig their visors or take off their breathig apparatus before the spray booth or room has cleared? Could exposure be occurrig some other way eg durig gu cleaig? Repair aythig that eeds it ad/or advise workers o usig the cotrols ad breathig apparatus the collect fresh samples. If the result is the first from a worker the it is sesible to ask for aother sample for cofirmatio. It should be oted that because the guidace value is based o the value foud i 9 out of 10 samples i places with good cotrol it is likely that 1 i 10 values will be above the guidace value eve i places with good cotrol. For Further Advice cotact: Sample Receptio, Health & Safety Laboratory, Harpur Hill, Buxto, SK17 9JN T E sample.registratio@hsl.gsi.gov.uk