handling aviation turbine fuels. Class I, Division 2
locations extend 25 feet (7.6 m) horizontally from any surface
of the device and upward 3 feet (0.9 m) above grade level.
Provide alarm devices on the ventilation systems for products
with a flash point below 100 degrees F (38 degrees C) (e.g.,
Class I liquids).
b) Outdoor locations and those indoor locations
having positive mechanical ventilation that are between 3 feet
(0.9 m) and 8 feet (2.4 m), extending in all directions, to
fill openings and vents on individual containers to which
Class I, Division 2 locations extend to 3 feet (0.9 m) above
grade and between 3 feet (0.9 m) and 10 feet (3 m)
horizontally to Division 1 zones.
c) Outdoor locations between 5 feet (1.5 m) and 10
feet (3 m) of the Division 1 zones at vents and openings, or
flammable or combustible liquid storage tanks.
d) Entire pit, sump, open trench, or other
depression, any part of which is within a Division 1 or 2
location and is provided with mechanical ventilation.
e) Outdoor locations within 3 feet (0.9 m) of the
fittings, meters, and similar devices that are located in
pipelines handling flammable or combustible liquids under
pressure. Class I, Division 2 locations extend upward 18
inches (450 mm) above grade level and within 10 feet (3 m)
horizontally from any surface of the device.
Locations within and extending upward to the top
of the dikes
that surround aboveground tanks containing
combustible liquids and within 10 feet (3 m),
all directions of the tank shell, ends, or roof.
g) Locations extending upward 18 inches (450 mm)
above grade level within 50 feet (15.2 m) horizontally from
any surface of API separators, whether installed indoor or