There’s a reason why both OSHA and EPA have requirements to CONTROL the entry of contractors into our covered process(s), their presence, and their exit from the process. It is so IMPORTANT, we find two (2) places in the standards that require this kind of CONTROL over contractors who wish to work ON, IN, or ADJACENT to our covered process…
(f) Operating procedures
…
(4) The employer shall develop and implement safe work practices to provide for the control of hazards during operations such as lockout/tag out; confined space entry; opening process equipment or piping; and control over entrance into a facility by maintenance, contractor, laboratory, or other support personnel. These safe work practices shall apply to employees and contractor employees.
and
(h) Contractors
…
(2) Employer responsibilities
(iv) The employer shall develop and implement safe work practices consistent with paragraph (f)(4) of this section, to control the entrance, presence and exit of contract employers and contract employees in covered process areas.
This story is 100% real and I am NOT exaggerating any aspect of it; the names have been left out to protect the company and contractor, but this actually happened in 2015!