PDFWAC 296-46B-450
Transformers and transformer vaults (including secondary ties).
027 Flammable-liquid or oil-filled transformers installed outdoors.
(1) Flammable-liquid or oil-filled transformers installed outdoors must meet the following requirements:
(a) A transformer installed adjacent to a building/structure with any combustible surface may be located only in the shaded "Approved Transformer Area" shown in Figure 450-1;
"Approved Transformer Area" shown in Figure 450-1;
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(b) A transformer installed adjacent to a building/structure with no combustible surface(s) may be located only in the shaded "Approved Transformer Area" shown in Figure 450-2;
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(c) In an area in which a transformer is to be installed next to a nonhabitable structure, the transformer may be no closer than two feet to the building/structure and must be outside a line extended vertically from the ends of the eaves or rooflines;
(d) A building/structure may have no doors, windows, stairways, or other openings closer than eight feet to the transformer;
(e) The finished grade at the location of the transformer must be such that any oil leaking from the transformer will flow away from the building/structure and will not pool; and
(f) If transformers are installed in areas subject to traffic other than pedestrian traffic, they must be provided with adequate guarding.
(2) Enclosures for total underground flammable-liquid or oil-filled transformers must not be located within eight feet of a doorway, operable window, stairways or fire escape. Adequate space must be maintained above the enclosure so that a boom may be used to lift the transformer from the enclosure.
[Statutory Authority: Chapter 19.28 RCW, RCW 19.28.031 and 19.28.251. WSR 24-05-085, § 296-46B-450, filed 2/21/24, effective 4/1/24. Statutory Authority: Chapter 19.28 RCW, RCW 19.28.010 and 19.28.031. WSR 17-12-021, § 296-46B-450, filed 5/30/17, effective 7/1/17. Statutory Authority: Chapter 19.28 RCW. WSR 13-03-128, § 296-46B-450, filed 1/22/13, effective 3/1/13. Statutory Authority: RCW 19.28.006, 19.28.010, 19.28.031, 19.28.041, 19.28.061, 19.28.101, 19.28.131, 19.28.161, 19.28.171, 19.28.191, 19.28.201, 19.28.211, 19.28.241, 19.28.251, 19.28.271, 19.28.311, 19.28.321, 19.28.400, 19.28.420, 19.28.490, 19.28.551, 2002 c 249, chapters 34.05 and 19.28 RCW. WSR 03-09-111, § 296-46B-450, filed 4/22/03, effective 5/23/03.]