Exposure modeling is no substitute for air monitoring. I didn't think I needed to say this in my May and June columns on modeling software. Unfortunately, I was surprised recently to hear an industrial hygienist mention that he modeled solvent exposures In a batch mixing operation because previous air monitoring results showed a wide range in employee exposures.

This hygienist somehow felt that modeling was more representative of worker exposure than actual air sampling results. This is a dangerous misapplication of modeling.

It's normal for air sampling exposure ...