PDFWAC 296-818-40010

Explosion venting and wiring.

You must follow the requirements in Table-3 for flammable or combustible dust mixtures.
Table-3: Explosion Venting and Wiring
If you have
Then
Flammable or explosive dust mixtures that may be present
Make sure the construction of equipment, including the exhaust system and all electrical wiring, meets both of the following:
 
• The American National Standard Installation (ANSI) of Blower and Exhaust Systems for Dust, Stock, and Vapor Removal or Conveying, NFPA 91. 2004.
 
• The electrical requirements for Class II locations in WAC 296-24-95613, located in Part L of chapter 296-24 WAC.
 
Make sure blast cleaning enclosures, the ducts, and the dust collector are constructed with either loose panels or explosion venting areas that meet all of the following:
 
• Provides pressure relief in case of an explosion.
 
• Are located away from occupied areas.
 
• The Guide for Deflagations, NFPA 68. 2002.
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, and 49.17.060. WSR 17-18-075, § 296-818-40010, filed 9/5/17, effective 10/6/17; WSR 06-12-074, § 296-818-40010, filed 6/6/06, effective 9/1/06.]