The National Fire Protection Association standard applicable to protective clothing, self-contained breathing apparatus, or personal alert safety systems is the standard in effect when a fire-fighting agency contracts to purchase the item. The agency may continue to use an item that was in use or contracted for before a change in a standard unless the commission determines that the continued use constitutes an undue risk to the wearer, in which case the commission shall order the use be discontinued and shall set an appropriate date for compliance with the revised standard.
Tex. Gov't. Code § 419.043