completed 12/2007
- detection and identification of polymeric isocyanates at workplaces - validation of alternative analytical methods for isocyanates - definition of safe PUR-workplaces
- air sampling at workplaces - air sampling at model workplaces - HPLC-analysis - HPLC-MS-analysis
Methodic studies of sampling and analytics: - It could be shown that the air samples within the range of 1-3 l/min have been independent from the active volume flow rate - The sampling time had a great impact on the results - Quasi-continuous methods are improper for the evaluation of work places. For the detection of emission sources they could be used - It is recommended to identify isocyanates with a material calibration Evaluation of the work place situation: - Slot jet application leads to lesser isocyanate exposition compared to barrel application - Humidity in the range of 20-50% show no significant influence on air concentration of isocyanates - In operational measurements monomer concentrations lower 0.1% lead to lower MDI air concentrations - The ambient temperature has no effect on the air concentration in the temperature range of 15-25°C - The processing temperature has a significant impact on the adhesive emissions - The local exhaust ventilation or the housing of sources leads to significant reduced MDI air concentration - With increasing distance to the emission source the isocyanats exposure decreases. While for single emission sources this effect is clearly observed, isocyanate emissions of multiple sources interfere. - The definition of a secured work place by means of distance to the emission source is not complete without consideration of the facility geometry and the knowledge of air supply and ventilation capacity.
-cross sectoral-
Type of hazard:dangerous substances, work-related diseases
Catchwords:analytical methods, chemical working substances
Description, key words:Isocynates, PUR-hotmelts, ordinance on hazardous substances, TRGS 430