California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 15 - Petroleum Safety Orders-Refining, Transportation and Handling
Article 15 - Process Equipment - Maintenance
Section 6838 - Process Equipment - Maintenance

(a) Scaffolding, staging or rigging shall not prevent safe access to the parts of a processing unit nor hamper the operation of, controls in case of an emergency, and shall be promptly removed when no longer needed.

(b) When wood or other combustible scaffolding, staging or rigging is erected near hot equipment, it shall be so spaced or insulated from such equipment that it will not ignite nor char by contact or by radiated heat.

(c) Vessel manhole covers which are installed vertically and which are not provided with hinges, davits or other means of support, shall be fitted with handles or other suitable means for connecting lifting devices when the absence of such devices constitutes a hazard.

(d) Where employees are required to enter a vessel through a manhole on the side or end of the vessel, and where the bottom of such manhole is over three feet six inches (3'6") above the ground or floor level, a temporary or a permanent platform shall be provided. Such platform shall be located not more than three feet six inches (3'6") below the bottom of the manhole through which entry is to be made.