Calculate the MUC for a 1/2 face respirator with a PEL of 50 ug/m3.

To determine the Maximum Use Concentration (MUC) for a respirator, the calculation typically involves the Permissible Exposure Limit (PEL) and the assigned protection factor (APF) for the specific type of respirator. In the case of a half-face respirator, an APF of 10 is commonly used, meaning that the respirator can reduce the concentration of contaminants in the air by a factor of ten.

Given that the PEL is 50 µg/m³, you can calculate the MUC by multiplying the PEL by the APF. So, in this case:

MUC = PEL x APF

MUC = 50 µg/m³ x 10

MUC = 500 µg/m³

This result indicates that the maximum concentration of the hazardous substance that a worker can be exposed to while wearing a half face respirator would be 500 µg/m³. This ensures that the concentration is kept within safe limits for the protection of the worker's health.