These requirements cover chemical, physical and performance properties of dry chemical fire extinguishing agents for use in portable fire extinguishing equipment being evaluated to CAN/ULC-S504M, Standard for Dry Chemical and Dry Powder Hand and Wheeled Fire Extinguishers.These requirements are also intended for the evaluation of recharge dry chemical fire extinguishing agents for use in extinguishers meeting the requirements of CAN/ULC-S504, provided the performance of the combination of the extinguisher and recharge agent, including performance during fire tests, can be shown to be equivalent to that of the original extinguisher.