6.3.2.16.Evaporative Air Coolers, Misters, Atomizers, Air Washers and Humidifiers

(1) Evaporative air coolers, misters, atomizers, air washers and humidifiers shall be designed in accordance with Sections 8 and 9 of ASHRAE Guideline 12, “Minimizing the Risk of Legionellosis Associated with Building Water Systems.” (2) Systems referred to in Sentence (1) shall (a) be designed so that water continuously circulates through all parts of the system that are normally wetted when the system is operating, and (b) incorporate a method of preventing water stagnation within the system itself and the internal plumbing when the system is not operating. (See Note A-6.3.2.16.(2)) (3) All components of systems referred to in Sentence (1), including filters and evaporation media, shall be constructed of corrosion-resistant, non-porous materials that do not promote the proliferation of disease-causing micro-organisms. (4) Associated sumps shall (a) be constructed of corrosion-resistant, non-porous materials that do not promote the proliferation of disease-causing micro-organisms, (b) include auxiliary drains to prevent the overflow of water into ductwork, and (c) be installed so that they can be flushed, drained, cleaned and disinfected. (5) Where misters, atomizers or air washers are used in ductwork, the affected duct section shall be (a) designed to ensure drainage of unevaporated and accumulated water, and (b) constructed of corrosion-resistant, non-porous materials that do not promote the proliferation of disease-causing micro-organisms. (6) Make-up water connections shall be equipped with backflow prevention devices that conform to Article 7.6.2.1. (See Note A-6.3.2.16.(6))