What test pressure should cartridge and cylinder operated dry chemical types be hydro tested at?

The correct answer is the original factory test pressure. This is the pressure at which the manufacturer tested the cylinder or cartridge before it was placed into service. Hydrostatic testing at this pressure ensures that the integrity and strength of the container are assessed accurately and verifies that it can safely hold the contents under pressure without any risk of failure.

Using the original factory test pressure as a benchmark is crucial because it reflects the design specifications and safety margins established by the manufacturer. This testing process is essential for maintaining safety standards and ensuring that the equipment remains functional and free of defects that could pose a hazard during use.

While current service pressure, maximum allowable pressure, and standard pressure are important metrics in evaluating equipment performance, they do not directly pertain to the specific pressure used for hydrostatic testing. Understanding the correct test pressure is pivotal in ensuring compliance with safety regulations and guidelines relevant to fire safety equipment.