The Ontario Building Code | Air Washers and Evaporative Cooling Sections or Towers
6.2.3.14. Air Washers and Evaporative Cooling Sections or Towers
(1) The filter and water evaporation medium of every air washer and evaporative cooling section enclosed within a building shall be made of noncombustible material.
(2) Sumps for air washer and evaporative cooling sections shall be constructed and installed so that they can be flushed and drained.
(3) Evaporative cooling sections or towers shall comply with the requirements of nfpa 214, "water-Cooling Towers".