Attmt 5 - NFPA 10 CH. 8.pdf

This document is a technical specification for hydrostatic testing procedures and requirements for fire extinguishers and their components. The specification establishes comprehensive standards for pressure vessel testing, personnel qualifications, equipment specifications, testing frequencies, procedures, and documentation requirements.

Personnel performing hydrostatic testing must be trained in pressure testing procedures and certified by an organization with an acceptable certification program to the authority having jurisdiction. Testing facilities with DOT requalification identification numbers (RIN) or TC certifications may perform hydrostatic testing without additional fire extinguisher technician certification. Hydrostatic tests must include both internal and external visual examinations of cylinders and use water or compatible noncompressible fluid as the test medium; air or gases cannot be used as the sole testing medium. All air must be vented prior to testing to prevent violent cylinder failure. Test pressure gauges must be certified accurate to ±0.5 percent, capable of being read within 1 percent of test pressure, and calibrated semiannually, with master gauges calibrated annually. Testing frequencies vary by extinguisher type, ranging from 5-year intervals for water, foam, and dry chemical types with stainless steel shells to 12-year intervals for dry chemical and dry powder cartridge-operated types. Low-pressure cylinders are tested at pressures specified on the nameplate or at factory test pressure not exceeding three times service pressure, while high-pressure cylinders (DOT 3A, 3AA, 3AL series) are tested at 5/3 service pressure. Cylinders and cartridges passing hydrostatic tests must be labeled with test date, pressure used, and technician identification. Condemned cylinders—whether DOT/TC specification or non-specification types—must be marked "CONDEMNED" and rendered unusable through puncturing, drilling, burning, cutting, or rendering threaded connections unusable. Fire extinguishers exhibiting dents, mechanical injury, corrosion, soldering/welding repairs, worn threads, pitting, excessive heat exposure, or material incompatibilities must be condemned or retested per Section 8.8. Hose assemblies with shutoff nozzles and high/low-pressure accessory hoses require hydrostatic testing at intervals matching the associated extinguisher or cylinder type.