Foam Application
Question: We want to collect a 15-20 minute Isocyanate sample to evaluate our workers exposure to isocyanates. What method should we use? Thank you G.S.
Answer: Hello G.S. Thank you for your question. Isocyanates are regulated at a ceiling limit of 0.020 ppm and TWA limit of 0.005 ppm (Ontario, Canada, 2017). You are asking about 15 min sampling, so we can only assume that you need to measure a ceiling value during brief application of isocyanate. In general, 15 minute samples have notoriously poor reproduction. This is due to the results being affected by the direction of the air draft, how much or little isocyanate product was used and even the worker’s habits. In other words you have high chance of getting a non-reproducible reading. To obtain a more accurate and representative picture, you may want to collect multiple short term samples on the same worker.
Air sampling cassettes
There are 3 methods that are generally used for assessment of di-isocyanates: OSHA 42/47, NIOSH 5525, and IsoCheck methods.
The IsoCheck method offers the best sensitivity, but it is difficult to find a lab that can perform this test. Unfortunately, we do not offer this test.
NIOSH 5525 offers sensitivity of 0.001 ppm for 15 min samples. This sensitivity is sufficient for the Short Term Sampling of such di-isocyanates like HDI, MDI, TDI and IPDI
OSHA 42/47 is the least sensitive and can detect only 0.005 ppm of isocyanates on a 15 min sample. This method is not recommended for short sampling.
If you need to complete an Isocyanate assessment, please contact us for a free, no-obligation quote.
Sincerely
LCS Laboratory
