WAC 296-46B-450
WAC 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;
(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;
(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.