Any area in the vicinity of: (1) a dipping or coating process and its drainboard, or (2) associated drying or conveying equipment, or (3) the interior of any exhaust plenum or any exhaust duct leading from the process, or (4) other associated equipment that might contain a flammable vapor concentration exceeding 25 percent of the lower flammable limit (LFL) during operation or shut-down periods.
