You must ensure that all wiring components and utilization equipment in hazardous locations are maintained in a dust-tight, dust-ignition-proof, or explosion-proof condition, as appropriate. There must be no loose or missing screws, gaskets, threaded connections, seals, or other impairments to a tight condition.
Wash. Admin. Code § 296-155-432
Statutory Authority: Chapter 49.17 RCW. 88-11-021 (Order 88-04), § 296-155-432, filed 5/11/88.