How often should water-based extinguishers be hydrostatically tested according to NFPA 10?

Water-based extinguishers, such as those containing water or foam, are required to undergo hydrostatic testing to ensure their structural integrity and performance during a fire emergency. According to NFPA 10, the standard for portable fire extinguishers, these types of extinguishers must be hydrostatically tested every five years. This testing involves subjecting the extinguisher to high-pressure conditions to check for leaks, corrosion, and overall functionality of the cylinder. Ensuring that these extinguishers pass the hydrostatic test is vital for the safety and reliability of the fire protection system.

Although other intervals exist for different types of extinguishers, the five-year requirement is specific to water-based models, aligning with the need for frequent assessments given their usage and potential wear over time.