e.
Is field assembly of critical parts practical?
f.
Hazardous locations to be avoided
g.
Accessibility if above ground
h.
Location of test box if below ground
i. Importance of coating the adjacent pipe if below
ground
j.
Vulnerability to short circuiting
Factor of safety on pull-out strength required has
to be engineered for the specific conditions
involved since no blanket provisions are fully
applicable to all cases. The requirement for
isolating flanges or couplings should be based on a
study of the conditions. If the new piping is a
short extension to an existing old piping system not
under cathodic protection, an isolating fitting
should be installed at the point of connection,
since the new piping will be anodic to the older
system. If the older system is under cathodic
protection, no isolating fitting should be used.
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3.3.1
Isolation Joints and Fittings
Isolating fittings, including main line isolating flanges and couplings,
shall be installed aboveground, or within manholes, wherever possible.
Where isolating joints must be covered with soil, they shall be fitted with
a paper joint cover specifically manufactured for covering the particular
joint, and the space within the cover filled with hot coal-tar enamel.
Isolating fittings in lines entering buildings shall be located at least
305 mm 12 inches above grade of floor level, when possible. Isolating
joints shall be provided with grounding cells to protect against
over-voltage surges or approved surge protection devices. The cells shall
provide a low resistance across isolating joint without excessive loss of
cathodic current.
3.3.2
Gas Distribution Piping
Electrical isolation shall be provided at each building riser pipe to the
pressure regulator, at all points where a short to another structure or to
a foreign structure may occur, and at other locations as indicated on the
drawings.
3.4
TRENCHING AND BACKFILLING
Trenching and backfilling shall be in accordance with [Section 02300
EARTHWORK] [_____].
3.5
TESTS AND MEASUREMENTS
3.5.1
Baseline Potentials
Each test and measurement will be witnessed by the Contracting Officer.
The Contractor shall notify the Contracting Officer a minimum of five (5)
SECTION 13110A
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