1. What are OELs?

1.1 Definition

OELs are defined for all possible routes of exposure by inhalation.

We distinguish between:

• the VLE, the limit value set for short-term occupational exposure of 15 minutes, which may be repeated during the working day;

• the STEL, the acceptable weighted average value for 8 hours of work per day, during a 40-hour working week and over a 40-year working life; the STEL includes all exposures over a day (note that for work lasting longer than 8 hours, an adjustment is made to adapt the STEL value to the actual working...