1 Scope
This document specifies a test method for the sampling and analysis of airborne organic isocyanate (NCO) compounds in workplace air. The method covers organic compounds containing free isocyanate functional groups, including monomeric, oligomeric, prepolymeric and polymeric isocyanates, and addresses the measurement of total isocyanate groups in air samples collected for the assessment of occupational exposure.
The method is suitable for personal air sampling in the breathing zone for the determination of time-weighted average concentrations over sampling periods ranging from approximately 10 min to 8 h, although it can be applied to shorter sampling periods with high isocyanate air levels. It can also be used for background or fixed-location air sampling; however, due to aerodynamic effects, samplers designed for personal sampling do not necessarily exhibit the same collection characteristics when used for other purposes. It covers the measurement of airborne organic isocyanates over a concentration range of approximately 0,1 µg/m3 to 140 µg/m3 for a nominal air sample volume of 15 l; under the conditions specified in this document, typical qualitative and quantitative detection limits correspond to approximately 0,07 µg/m3 and 0,3 µg/m3, respectively, for a 15 l air sample.
This document does not apply to the simultaneous determination of isocyanates and amines, nor to modified methods employing alternative sampling devices or detection techniques not described in this document.