26 September 2006
7.6 m (25 ft) from a transformer containing more than 19 m3 (5,000
gallons) where roofs are less than 15 m (50 ft) high.
For equipment, barriers must extend 0.3m (1 ft) vertically and 0.6m (2 ft)
horizontally beyond transformer components that could be pressurized as the
result of an electrical fault. This will typically include bushings, pressure relief
vents, radiators, tap changer enclosures, and other similar devices.
6-220.127.116.11.3 Water Spray Exposure Protection.
If water spray or automatic sprinkler protection is used for
building protection, a discharge density of 8.2 L/min/m (0.20 gpm/ft) must be
used over the exposed surface.
The water supply must be adequate for 2 hours and must
include a hose stream demand of 1900 L/min (500 gpm).
For multiple transformer installations the water spray system
must be designed based on simultaneous operation of the water spray systems
for the adjacent transformers.
Design the water spray system to provide a density of 10.2
L/min/m (0.25 gpm/ft) over transformer surfaces, except areas under the
transformer in accordance with FM Global Data Sheet 4-1N, Water Spray Fixed
When the ground around the transformer is non-absorbing,
water spray must be provided at a density of 6.1 L/min/m (0.15 gpm/ft) for the
diked area or for a distance of 3 m (10 ft) from the transformer in all directions.
Components of the water spray system, such as piping,
spray nozzles, and other components must be a minimum of 45.7 cm (18 in) from
Piping must not pass over the top of the transformer or be
exposed by tank relief vents.
Do not direct water spray nozzles at bushings.
TRASH COLLECTION AND DISPOSAL FACILITIES.
Central Trash Collection and Dumpsters.