Ariz. Admin. Code § R11-1-1632
When extreme heat conditions exist, sufficient cooling time shall be allowed before persons are allowed to enter converters, roasters, and reactors. Protective clothing shall be used when applicable. A supervisor shall be present when workers are in the vessel and determine when the vessel has cooled sufficient to allow safe access.
Adopted effective April 7, 1976 (Supp. 76-2).