UL is seeking Canadian Representation for the Canadian Standard ANSI/CAN/UL 973 Standard for Automatically Operated Roof Vents for Smoke and Heat.

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 UL is looking for Canadian representation from the Fire discipline for this standards development committee.  Meetings are generally held by video conference.

 UL is in the process of expanding the Standards Technical Panel (STP) for STP 793, Smoke and Heat Vents, and developing the new Canadian standard ANSI/CAN/UL 793, Standard for Automatically Operated Roof Vents for Smoke and Heat.  UL is working with the Standards Council of Canada (SCC) to develop this binational standard for Canada and the US.  UL 793 is currently an ANSI Standard in the USA and it is in its third edition. There are currently no requirements for this type of equipment in Canada.

The UL 793 standard is necessary in order to address the risks associated with automatically operated roof vents for smoke and heat that fall into two general categories: mechanically-opened and gravity-opened. Mechanically-opened vents consist primarily of a body frame, one or more damper covers and hatches, and operating mechanisms which generally include a heat responsive device and spring(s). Gravity-opened vents consist primarily of a body frame and non-metallic drop-out panel. The vents covered by these requirements are operated manually or automatically in the event of fire to remove smoke and heat from the building. Automatic operation does not depend on electrical power or other energy sources that may be interrupted during a fire, but rather depends upon operation of a heat responsive device or on the action of a plastic cover shrinking and falling from place due to fire exposure, or the like. These vents are not intended for use as general purpose building ventilation devices.

If you want to apply to join this STP, you can do so at:


Thank you in advance for your assistance and please contact us if you should have any questions or comments.

Article Submitted by:

Brian McBain, GIFirE
Senior Regulatory Services Representative
Distinguished Member of Technical Staff – William Henry Merrill Society
Codes and Regulatory Services
Building & Life Safety Technologies
Underwriters Laboratories of Canada Inc.
171 Nepean Street, Suite 400
Ottawa, ON, K2P 0B4 Canada