OSHA comments from the January 19, 1989 Final Rule on Air Contaminants Project extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.

PLATINUM (METAL)

CAS: 7440-06-4; Chemical Formula: Pt

       OSHA had no former limit for platinum metal. The proposed PEL was 1 mg/m3, and this limit is established in the final rule. NIOSH (Ex. 8-47, Table N1) agreed that this PEL is appropriate. The ACGIH hasa limit of 1.0 mg/m3 TWA for platinum metal dust. Platinum is a silver-gray, lustrous, malleable, ductile precious metal.

       Based on the TLV for platinum soluble salts and the absence of any severe health effects associated with exposure to the metal dust, the ACGIH recommended a TLV of 1.0 mg/m3 for platinum metal dust. This limit reflects good industrial hygiene practice and acknowledges that heavy metal dusts are more toxic than nuisance dusts (which are controlled to 10 mg/m 3). No comments (other than that of NIOSH) were received.

       OSHA is establishing an 8-hour TWA limit of 1.0 mg/m3 for platinum metal. The Agency concludes that this limit will protect workers against the significant risk of adverse health effects potentially associated with workplace exposures to this substance at the levels permitted by the absence of any OSHA PEL.