(a) An approach channel must be unobstructed and have a minimum length of 4.0 feet before the first ultraviolet (UV) bank.(b) The downstream channel length must be unobstructed for a minimum length of 4.0 feet following the last bank of UV lamps and before a fluid-level control device.(c) Inlet channels must provide equal flow distribution across all UV channels.(d) A downstream discharge point of a UV system must include a level control that ensures that the UV lamps remain submerged, according to the manufacturer's recommendations, regardless of flow.(e) The UV system must prevent an individual's exposure to UV light from the UV system, including upstream and downstream portions of a UV channel.(f) An enclosed UV system must have a dehumidifier or must be designed to prevent corrosion of electrical components.