What type of extinguishers does the 5-year hydrostatic test interval apply to?

The 5-year hydrostatic test interval applies to stored pressure fire extinguishers. This requirement stems from the need to ensure the integrity and safety of the extinguisher's pressure vessel. Over time, factors such as corrosion and wear can affect the structural integrity of the extinguisher. Therefore, the hydrostatic testing process is crucial as it involves pressurizing the extinguisher beyond its normal operating pressure to identify any weaknesses or leaks.

Stored pressure extinguishers, which include various types of agents, are commonly found in many settings because of their ease of use and effectiveness. In contrast, while dry chemical extinguishers and CO2 extinguishers have their own inspection and maintenance protocols, their hydrostatic testing intervals are different and typically follow different regulations. Water extinguishers with antifreeze also have their specific testing requirements, often related to the presence of antifreeze agents rather than the standard hydrostatic testing. This highlights the specialized nature of amusement within the industry regarding maintenance protocols and testing intervals for various types of extinguishers.