ULC 503

This is the common UL and ULC Standard for Carbon-Dioxide Fire Extinguishers. It is the Fourth edition of CAN/ULC-S503, and the Ninth edition of ANSI/UL 154. These requirements cover the construction and performance, exclusive of performance during fire tests, of portable carbon-dioxide fire extinguishers. Carbon-dioxide fire extinguishers are intended to be utilized in accordance with the Standard for Portable Fire Extinguishers, NFPA 10 and the National Fire Code of Canada. The requirements for performance during fire testing of carbon-dioxide fire extinguishers are specified in the Binational Standard for Rating and Fire Testing of Fire Extinguishers, ANSI/UL 711/CAN/ULC-S508.