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Part 9 Confined Spaces
Confined Spaces Definitions
9.1 Definitions
In this Part
"adjacent piping" means a device such as a pipe, line, duct or conduit which is connected to a confined space or is so located as to allow a substance from within the device to enter the confined space;
"blank" means a solid plate installed through the cross-section of a pipe, usually at a flanged connection;
"blanking or blinding" means the absolute closure of adjacent piping, by fastening across its bore a solid plate or cap that completely covers the bore and that is capable of withstanding the maximum pressure of the adjacent piping;
"blind" means a solid plate installed at the end of a pipe which has at that point been physically disconnected from a piping system;
"clean respirable air" when used to describe the atmosphere inside a confined space, means an atmosphere which is equivalent to clean, outdoor air and which contains
(a) about 20.9% oxygen by volume,
(b) no measurable flammable gas or vapour as determined using a combustible gas measuring instrument, and
(c) no air contaminant in concentrations exceeding either 10% of its applicable exposure limit in Part 5 (Chemical Agents and Biological Agents) or an acceptable ambient air quality standard established by an authority having jurisdiction over environmental air standards, whichever is greater;
"confined space", except as otherwise determined by the Board, means an area, other than an underground working, that
(a) is enclosed or partially enclosed,
(b) is not designed or intended for continuous human occupancy,
(c) has limited or restricted means for entry or exit that may complicate the provision of first aid, evacuation, rescue or other emergency response service, and
(d) is large enough and so configured that a worker could enter to perform assigned work;
[Amended by B.C. Reg. 381/2004, effective January 1, 2005.]
"disconnecting" means physically disconnecting adjacent piping from a confined space to prevent its contents from entering the space in the event of discharge;
"double block and bleed" means the closure of adjacent piping by locking out a drain or vent in the open position in the line between 2 locked out valves in the closed position;
"harmful substance" means a WHMIS controlled product, a substance referred to under section 5.48, or a substance which may have a harmful effect on a worker in a confined space;
"high hazard atmosphere" means an atmosphere that may expose a worker to risk of death, incapacitation, injury, acute illness or otherwise impair the ability of the worker to escape unaided from a confined space, in the event of a failure of the ventilation system or respirator;
"inerting" means intentionally flooding the atmosphere inside a confined space with an inert gas such as nitrogen to eliminate the hazard of ignition of flammable vapours inside the confined space but thereby creating an oxygen deficient atmosphere;
"low hazard atmosphere" means an atmosphere which is shown by pre-entry testing or otherwise known to contain clean respirable air immediately prior to entry to a confined space and which is not likely to change during the work activity, as determined by a qualified person after consideration of the design, construction and use of the confined space, the work activities to be performed, and all engineering controls required by this Regulation;
"moderate hazard atmosphere" means an atmosphere that is not clean respirable air but is not likely to impair the ability of the worker to escape unaided from a confined space, in the event of a failure of the ventilation system or respirator.
[Amended by B.C. Reg. 315/2003, effective October 29, 2003.]
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