CIP10 optimization for 4,4-methylene diphenyl diisocyanate aerosol sampling and field comparison with impinger method.

4,4-methylene diphenyl diisocyanate (MDI) aerosol exposure evaluation in spray foam insulation application is known as being a challenge because the spray foam application actually involves a fast-curing process. Available techniques are either not user-friendly or are inaccurate or not validated for this application. To address these issues, a new approach using a CIP10M was developed to appropriately collect MDI aerosol in spray foam insulation while being suitable for personal sampling.

Investigation of the competitive rate of derivatization of several secondary amines with phenylisocyanate (PHI), hexamethylene-1,6-diisocyanate (HDI), 4,4'-methylenebis(phenyl isocyanate) (MDI) and toluene diisocyanate (TDI) in liquid medium.

The stabilization of the isocyanate (NCO) groups during workplace sampling is necessary for their subsequent laboratory analysis. Most derivatization reagents are secondary amines. By carrying out a test in which two secondary amines are added to an isocyanate, the relative rates of these reactions can be evaluated.

Evaluation of the SureSpot direct-reading instrument for the determination of polymeric MDI aerosols.

Recent studies in our laboratories have focused on the reliability of direct-reading instruments for the determination of airborne isocyanate concentrations. The evaluation of airborne isocyanates is complicated because these substances exist as diisocyanate monomers and polyisocyanate oligomers, both in the vapor and aerosol phases. The studies showed that a number of direct-reading instruments, including the SureSpot test kit, do not allow an accurate determination of isocyanates in the aerosol phase.