Fire extinguisher CO types have the test information stamped on the cylinder, all other types get a sticker on the back of the cylinder. Once dry, the units are recharged. Unlike the UK, the US does not rebuild extinguishers and replace valves at specific intervals unless parts are found to be defective, with the exception of halon. Halon types are often given new o-rings and valve stems at every internal maintenance to minimize any leakage potential. OEM equipment must be used for replacement parts for the extinguisher to maintain its UL rating. If parts are unavailable, replacement is recommended, keep in mind
Fire extinguisher a distance). Such signs may be manufactured from a variety of materials, commonly self-adhesive vinyl, rigid PVC, and aluminum. In addition to words and pictographs indicating the presence of a fire extinguisher, some modern extinguisher identification signs also describe the extinguishing agent in the unit, and summarize the types of fire on which it may safely be used. Some public and government buildings are often required, by local legal codes, to provide an identification sign for each extinguisher on the site. Similar signs are available for other fire equipment (including fire blankets and fire hose reels/racks), and for other emergency