When medical surveillance or monitoring is indicated (such as hearing exams, respiratory protection evaluations, or evaluation/treatment for exposure to toxic substances), the host employer must offer and perform the required medical surveillance or evaluations. The staffing agency must ensure that the records of the required medical surveillance or evaluations are maintained in accordance with the appropriate OSHA standards.

This means the temporary staffing agency is required to maintain cumulative exposure data (e.g., 30-day lead exposure, 6-month noise exposure, etc.), when the employee works for several different companies during the year. But, each of those host companies would have responsibilities for ensuring the workers were following proper procedures, wearing appropriate PPE, etc., and to communicate to the host employer (ideally before work begins) that workers will be exposed to such hazardous conditions.