Quick Links
- View CSA Standards referenced in OHS Regulation New!
- WorkSafeBC Store
- Library Services
- Workers Compensation Act
- Hazardous Products Act
- Quick Reference Guide: Hazardous Products Act
- Controlled Products Regulations
- Notice of Project
- Variances to the OHS Regulation
- Research
- Order printed copy of OHS Regulation from Crown Publications
Customer Centres
Part 9 Confined Spaces
Cleaning, Purging, Venting, Inerting
9.27 Cleaning, purging and venting
(1) When practicable, the employer must ensure that a confined space to be entered contains clean respirable air.
(2) If a confined space is known, or shown by pre-entry testing to contain other than clean respirable air, the hazard must be controlled by cleaning, purging or venting the space and the atmosphere must be retested before a worker enters the space.
(3) The dead-ends of a line that has been isolated must be cleaned, purged or vented to remove any harmful substance which could present a hazard to a worker entering the confined space.
9.28 Risk control
If clean respirable air cannot be assured in a confined space before worker entry, the employer must ensure that
(a) all workers entering the space wear appropriate personal protective equipment including respirators when necessary
(b) the concentrations of flammable gases and vapours are maintained below 20% of the lower explosive limit, and
(c) if flammable or explosive gases, vapours or liquids are present, all sources of ignition are eliminated or adequately controlled.
9.29 Inerting
(1) The employer must notify the Board in writing, and submit a copy of the proposed work procedures, at least 7 days before a worker enters a confined space which has been inerted.
(2) The employer must follow any additional precautions that are prescribed by the Board after review of the notification.
(3) If a confined space has been inerted
(a) all entry precautions for high hazard atmospheres must be followed, except the requirement for continuous ventilation,
(b) every worker entering the confined space must be equipped with supplied-air respiratory protection meeting the requirements of Part 8 (Personal Protective Clothing and Equipment),
(c) all ignition sources must be controlled, and
(d) the atmosphere inside the confined space must remain inerted while workers are inside.
(4) Subsection (1) does not apply to entry for the purpose of performing emergency rescue duties.
You can return to the Top of this page
Disclaimer: WorkSafeBC ("Workers' Compensation Board of B.C.") publishes the online version Occupational Health and Safety Regulation ("OHS Regulation") in accordance with its mandate under the Workers Compensation Act to provide information and promote public awareness of occupational health and safety matters. The online OHS Regulation is not the official version of the OHS Regulation, which may be purchased from Crown Publications.
WorkSafeBC endeavours to update the online OHS Regulation as soon as possible following any legislative amendments. However, WorkSafeBC does not warrant the accuracy or the completeness of the online OHS Regulation, and neither WorkSafeBC nor its board of directors, employees or agents shall be liable to any person for any loss or damage of any nature, whether arising out of negligence or otherwise, arising from the use of the online OHS Regulation.
Employers are legally obligated to make a copy of the Workers' Compensation Act and the OHS Regulation readily available for review by workers. The circumstances under which WorkSafeBC may consider an employer's providing access to electronic versions of the Act and OHS Regulation to have satisfied this obligation are described in Guideline G-D3-115(2)(f).