According to OSHA, maximum permissible amount of Ni in dental clinic environment is?

The former OSHA Permissible Exposure Limit for all forms of inorganic nickel (as Ni) was 1 mg/m3 TWA. Based on the ACGIH recommendation, OSHA proposed revising this limit to 0.1 mg/m3 TWA; this limit is established in the final rule. NIOSH recommends that exposure to any form of inorganic nickel be maintained at or below 0.015 mg/m3. Ref: https://www.cdc.gov/niosh/pel88/7440-02.html#:~:text=The%20former%20OSHA%20PEL%20for,below%200.015%20mg%2Fm3.