Evening all, I need your advice, when undertaking COSHH assessments I'm clear that you use the MSDS to get the information but what I can't get my head around is how you work out the PPM/MGm3? Do you need to use equipment such as stain tubes? Or can you work this out theory based without undertaking practical samples? The reason I ask is the likelihood of taking samples of exposure is limited. I'd like some guidance on how to undertake the assessments with the factors above. Thanks Barney#1

Barney Stain tubes may give you some idea of what the exposures are but, unless you are using long-term tubes, they will only give spot readings, when what you are usually interested in is 8-hour average exposures. Also, do read the information supplied with the tubes as they can be subject to cross-sensitivity, which can mislead you. Depending on the situation, you may need assistance from a competent occupational hygienist; you can find one here: http://www.bohs.org/OHServices-directory/# LB

Agreed, stain tubes are at best a rough indicator - indicating whether there may be something or nothing to worry about. But useless for many substances. For some exposures, theory and observation may be adequate to assess the risk, for others a more accurate exposure assessment is necessary. Leadbelly's link to BOHS and hygienists is good advice.

Thank you for your replies everyone. This is my dilemma, I know how to work out the exposure when I've got the data but I'm just struggling on how you go about getting that data. A good example would be cleaning products in an office environment, how would you get the exposure data in that instance? My understanding is that there are exposure limits set out on the data sheets and also in EH 40 but it's getting the levels that are given off in a given situation I just can't get my head around. Barney#1

I agree with Kate For office environments, I wouldn't be measuring any atmospheric substances - initially working on a number of issues cleaning material present when used quantity used history of complaints about MSDS information As Kate says just seek reassurance that the products are being used in the correct way. Using the CoSHH hierarchy of controls - air sampling is way down the list. A while since I have done much on CoSHH in an occupational sense, but doesn't the hierarchy of controls go something like* Eliminate Substitute Full enclosure Partial Enclosure Natural ventilation Forced ventilation Safe system of work / use Air monitoring etc * other hierarchy lists are available In my experience, even in workshops/engineering situations - unless a hazard substance is in use, then experience and design standards are used before air sampling

Barney, good advice from Kate, JJ and others; it's not always necessary to quantify/monitor exposure. If it's a nasty like H2S yes, but in your environment I think you can follow the COSHH Essentials tool/method on the HSE website, which allows you make an assessment/judgement based on volatility, quantity, temperature, risk phrases etc and for your job I expect 'good general ventilation' will be the recommendation. So a 'possible solution' might be: if the cleaning products can be smelled in the office provide better ventilation by opening doors and windows. That's a possible simple solution that might be arrived at through the COSHH Essentials tool. COSHH Essentials might seem complicated but you can, with a bit of thought while studying that guidance, work out your own tool/flowchart on paper or spreadsheet that helps you make the decisions.

As others have said it is unlikely that there are any volatile components in standard office cleaning products that pose any significant health risk. In a normal well ventilated office, the level of substance in the atmosphere should never get anywhere near the WEL. If you are concerned, eg the office is small and poorly ventilated, and then you can get a guesstimate using the formulas available on the HSE website. Chris’s point about the main risk being skin exposure is a good one.

Barney, When conducting a COSHH assessment be sure to follow the Principles of Good Practice contained with the COSHH L5 guidance – Schedule 2A. As for the measuring I would not recommend anybody tackling this if they have not had any recognised Occupational Hygiene training. If you feel this is something you need looking at your location in Merseyside I know a very good provider in Chester (PM me if you would like the details as they also offer a consultancy service). If there are exposure limits specified in the EH40 then remember these limits are only relevant to the inhalable fraction so personal monitoring would have to be carried out to obtain a measurement (if deemed necessary!). Personal monitoring will not measure any other routes of exposure other than inhalation. On the contrary the EH40 does contain a few limits or values for biological monitoring (BMGV). This method is particularly useful when using substances with an ingestion, inhalation and skin absorption risk, i.e. ingestion in some cases can still occur through the inhalation process. Usually you can get a good indication of exposure using a basic survey – e.g. fully enclosed extracted processes will not pose significant risk if the controls are adequately maintained. Visual aids such as Tyndal Illumination, Smoke Tubes, Grab Samples (Colorimetric Indicators) etc can help to assess the situation and give a good indication. Finally I stand by my number one rule before doing any COSHH Assessment – read the Principles of Good Practise and be sure you think outside the box. The MSDS will give you information for 1 part of the COSHH Assessment – you have to consider what may be generated by the process. I.e. (Wood + Saw = Dust) (Metal + Heat = Fume) If you would like any further information drop me an email to explain in the brief the products and application and I will have a quick look for you. Regards Kev

Morning Chris, An excellent example – it just shows in the world of chemical safety how deep a plot can thicken. Your example also states the importance of keeping the assessment to a personal level. The effected individual (although not occupational) would have had to have controls implemented to protect him / her from their identified condition as not to agitate it further. Thanks for sharing! Kev