Skip to Main Content


This information is provided free of charge by the Department of Industrial Relations from its web site at www.dir.ca.gov. These regulations are for the convenience of the user and no representation or warranty is made that the information is current or accurate. See full disclaimer at https://www.dir.ca.gov/od_pub/disclaimer.html.
 
Subchapter 7. General Industry Safety Orders

Group 26. DIVING AND PRESSURIZED WORKSITE OPERATIONS

ARTICLE 154. PRESSURIZED WORKSITE OPERATIONS

Return to index
New query

§6074. Definitions.



The following definitions shall apply in the application of these Orders.
Air Lock (Personnel): A chamber through which employees pass from one air pressure environment into another.
Bulkhead: An airtight structure separating the working chamber from free air or from another chamber under a different pressure than the working pressure.
Caisson: A wood, steel, concrete or reinforced air and water-tight chamber in which it is possible for employees to work under air pressure greater than atmospheric pressure.
Compressed Air Environment (Hyperbaric Condition): A work site where the ambient pressure is greater than the atmospheric pressure at the entrance to the work site.
Decanting (surface decompression): A method used for decompressing under certain circumstances. In this procedure the workers are brought to atmospheric pressure with a very high gas tension in the tissues and then immediately re-compressed in a second and separate chamber or lock.
Division: The current Division of Occupational Safety and Health, any predecessors, or any subsequent successor agency.
Emergency Locks: A lock designed to hold and permit the quick passage of an entire shift of employees.
High Air: Air pressure used to supply power to pneumatic tools and devices.
Low Air: Air supplied to pressurize working chambers and locks.
Materials Lock: An air lock through which materials and equipment pass from one air pressure environment into another.
Hyperbaric Chamber: A chamber in which employees are treated for decompression sickness and/or air embolism. It may also be used in pre-employment physical examinations to determine the adaptability of the prospective employee to changes in pressure.
Pressure: A force acting on a unit area. Usually shown as pounds per square inch (psi).
Absolute Pressure (psi): The sum of the atmospheric pressure and gauge pressure (psig).
Ambient Pressure: Encompassing pressure surrounding all sides.
Atmospheric Pressure: The pressure of air at sea level, usually 14.7 psi (one atmosphere), or 0 Psig.
Gauge Pressure (psig): That pressure measured by a gauge and indicating the pressure exceeding atmospheric.
Safety Screen: An air- and water-tight diaphragm placed across the upper part of a compressed air tunnel between the face and bulkhead, in order to prevent flooding the crown of the tunnel between the safety screen and the bulkhead, thus providing a safe means of refuge and exit from a flooding or flooded tunnel.
Special Decompression Chamber: A chamber to provide greater comfort for employees when the total decompression time exceeds 75 minutes.
Supervising Physician: A physician licensed in the State of California who is familiar with and experienced in the physical requirements for the medical aspects of work in compressed air environments.
Working Chamber: The space or compartment under air pressure in which the work is being done.


Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.

 HISTORY 
   
1. New section filed 4-4-2006; operative 5-4-2006 (Register 2006, No. 14).

2. Repealer of definition of "Normal Condition" and new definition of 
"Supervising Physician" filed 3-10-2010; operative 4-9-2010 (Register 2010, 
No. 11).

Go BackGo Back to Article 154 Table of Contents