Lead enters the body in two main ways:
Inhalation - Breathing lead fumes or dust
Ingestion - Swallowing lead dust
How is lead exposure measured?
PEL: You are allowed to be exposed up to the P ermissible E xposure L imit established by OSHA of 50 ug/m3 based on an 8 hour time weighted average.
Action Level: OSHA established an Action Level of 30 ug/m3 (micrograms per cubic meter of air) based on an 8 hour time weighted average. At this level, additional requirements of the Lead Standard must be implemented for example: exposure monitoring, medical surveillance (blood tests) and additional training.
Exposure Assessment: If there is a potential exposure to lead during construction activities, maintenance activities, brick moving, soldering etc., an exposure assessment (evaluation) must be performed to determine if the OSHA Action Level will be exceeded.
Sampling the air that the worker breathes can be performed or the potential exposure level can be predicted based on past air sampling results collected at similar jobs. Certain construction tasks (ie: grinding on lead painted surfaces) have been assigned potential exposure level values by OSHA.
You can observe the air monitoring process.