1. (1) You must ensure that, on a pneumatic dust collection system, each fabric dust filter collector has a monitoring device that will show a pressure drop across the surface of its filter.

2. (2) You must ensure that each filter collector installed after March 30, 1988, is:

   1. (a) Located outside the facility; or
   2. (b) When located inside the facility, protected by an explosion suppression system; or

   3. (c) Isolated by a structure with at least a one hour fire-resistance rating:

      1. (i) Next to an exterior wall;
      2. (ii) Vented to the outside; and
      3. (iii) The vent and ductwork must resist rupture from intense heat.

[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, and 49.17.060. WSR 17-16-132, § 296-99-060, filed 8/1/17, effective 9/1/17. Statutory Authority: Chapter 49.17 RCW. WSR 97-22-065, § 296-99-060, filed 11/3/97, effective 1/1/98; WSR 88-23-054 (Order 88-25), § 296-99-060, filed 11/14/88.]