Posted By angelae
Hoping someone can help me out here.
We (myself and our Occ Physician) have discovered today that we have an engineering workshop on site where they hand paint with paint containing isocyanates. Having looked at the MSDS for these paints they're respiratory sensitisers.
I already carry out annual lung function screening on these workers, but the area they are working in is open for all to enter, no respiratory protection etc.
Can anyone please advise if the risk from exposure to isocyanates would be any less because they're not spray painting? I've only ever come across people spray painting them, so this is a new one for me! Any advice would be greatly appreciated.
Thanks

Posted By garyh
In COSHH, you have to consider routes of exposure. Spraying Isocyanates is a particular issue as you are open to two routes ie

- skin / eye contact
- inhalation

The nub of this is that the act of spraying (ie using compressed air to disperse and then project this onto the item surface) exposes the operator to both routes without the need for direct contact.

Therefore, for hand painting, the inhalation route would be unlikely.

HSE info suggests that hand application may not give rise to exposure http://www.hse.gov.uk/re...hsl_pdf/2005/hsl0560.pdf

However, I would be cautious. To reassure yourself could you get a measurement(s) made to rule out inhalation?

What about other solvents present which may have a high vapour pressure (and so give off vapour which may be inhaled).

As a minimum I would go for ventilation (preferably LEV). Incidentally why not talk to the paint manufacturer?

Hope this helps.

Posted By Chris Packham
Angela

It isn't just respiratory exposure that you need to be concerned about. There is now evidence that skin exposure to isocyanates, and particularly MDI, can cause sensitization leading to asthma as well as allergic contact dermatitis.

What other constituents are there in the paint? If, as I suspect, it is solvent based, then there is a risk of skin uptake unless appropriate precautions have been taken.

I would assume that gloves are being worn, but you will need to check that these are appropriate. This is not quite as simple as might appear. Manufacturer's published performance data for chemical protective gloves is not adequate for the selection and use of such gloves, since it is based on a laboratory test according to a flawed standard. You will need to consider factors such as concomittant degradation, temperature, flexing, etc., all of which can significantly affect glove performance.

Chris

Posted By Chris Packham
Angela

Vinyl is totally inappropriate as a glove material for the mixture you describe. Nitrile will perform slightly better, but I have studies showing permeation breakthrough with nitrile gloves in just a few minutes.

Wearing the wrong glove can be worse than wearing no glove at all. The occlusion underneath the glove reduces the skin barrier so that any chemical inside the glove (and with thin vinyl this breakthrough will happen in seconds) can penetrate the skin and cause real damage.

Given the constituents of the paint I feel that there is a very significant risk of damage to health which needs addressing urgently.

If you feel you would like to discuss this give me a call on 01386 832 311

Chris