to control flow and to permit isolation of equipment for
maintenance or repair. Provide additional valves at required
Provide manually operated valves, except where motor operators
are specifically authorized by applicable standard drawings or
technical specifications. As a minimum requirement, provide
block valves at the following locations:
a) On each branch line at the point of connection to
the main product pipeline or header.
b) On the product pipeline or header just before the
line leaves a pumping station.
c) On the inlet and outlet connection of each line
strainer, filter/separator, meter, automatic valve, and other
equipment that requires periodic servicing. One inlet valve
and one outlet valve may be used to isolate more than one
piece of adjacent equipment which are connected in series.
d) On the upstream and downstream side of each line
e) On each main distribution pipeline immediately
downstream of the branch connection to each existing or future
operating storage facility served by the pipeline.
f) At intermediate points of approximately 10 miles
isolation of a section of the line for maintenance and repair.
g) On each side of water crossing exceeding 100 feet
(30 m) in width, and near the shoreline of a submerged sea
where pipeline is piggable and absolute shut-off is not
required such as item (d) above.
runways, taxiways, and roadways.
j) For low-point drains and high-point vents.