UL 2166 2021 pdf download – Halocarbon Clean Agent Extinguishing System Units.
7 General 7.1 After discharge of the extinguishing agent is initiated, an extinguishing system unit shall maintain the maximum rate of application of the extinguishing agent without requiring a manual action. 7.2 All exposed parts of an extinguishing system, including the finishes on coated or painted parts, the assemblies of moving parts, the nameplates as secured in place, the mounting bracket, or other similar parts, shall be resistant to commonly encountered atmospheric corrosive influences, and to galvanic corrosion, as determined by the Salt Spray Corrosion Test, Section 29. 7.3 When the deterioration, breakage or other malfunction of a material for an extinguishing system unit presents a risk of causing the extinguishing system to become inoperable, the material shall not be susceptible to stress cracking. See 10-Day Moist Ammonia Air Stress Cracking Test, Section 53. 7.4 As covered by these requirements, an extinguishing system unit consists of: a) Actuating assemblies; b) An extinguishing agent storage container and valve assembly; c) Discharge nozzle(s); d) Indicators that show the condition of the extinguishing system; e) A means for mounting the extinguishing system; f) Manifold check valves; g) Remote manual controls; h) Selector valves; and/or i) Other accessory equipment. 7.5 Where U. S. customary units are employed, the minimum storage temperature of an extinguishing system unit shall be 35° F (1.7° C) or higher in increments of 5° F (2.8° C) up to a maximum of 65° F (18.3°C); 32°F (0°C), 0°F (minus 17.8°C), or lower in increments of 10°F (5.5°C); and a maximum storage temperature of either 100°F (37.8°C), 120°F (48.9°C), 130°F (54.4°C), or higher in increments of 10°F (5.5° C), except that the 100° F (37.8° C) maximum storage temperature applies to an automatic extinguisher unit only.
7.6 Where SI (System International) units are employed, extinguishing system units shall have a minimum storage temperature of 1.7°C (35°F) or higher in increments of 2.8°C (5°F) up to a maximum of 18.3°C (65°F); 0°C (32°F), -20°C (minus 4°F) or lower in increments of 5°C (9°F); and a maximum storage temperature of 37.8°C (100°F), 50°C (122°F), or higher in increments of 5°C (9°F), except that the 37.8°C (100°F) maximum storage temperature applies to an automatic extinguisher unit only. 7.7 When used as part of a multiple unit system, an extinguishing system unit shall be provided with a means for simultaneous operation of all system units. 7.8 The design concentrations for an extinguishing system unit and an automatic extinguisher unit shall be in accordance with the Standard for Clean Agent Fire Extinguishing Systems, NFPA 2001. Also, compliance with the Class A and Class B Fire Extinguishing Tests described in Section 35, and Nozzle Distribution Verification Tests described in Section 36, shall be demonstrated.