Answers and Illustrations Given
Minimum vertical height for a Type B-W gas vent above the bottom of a wall
furnace? - ✔✔12 Feet
NFPA 54 12.7.2(3)
Minimum thickness of a steel striker barrier for gas tubing protection? -
✔✔0.0508"
NFPA 54 7.3.4
What is the maximum temp that a clay flue liner must be able to withstand
without cracking? - ✔✔1,800 degrees F
NFPA 54 12.6.1.3
Combustion air obtained from indoors on the same story shall have a minimum
of... - ✔✔Two openings. Each opening 1in squared/1000 btu/hr of all appliances
in space
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,NFPA 54 9.3.2.3
When gas is being supplied by a manifold located in a remote area, what is the
maximum distance the shutoff valve at the manifold can be located from the
appliance? - ✔✔50 feet
NFPA 54 9.6.4.3
What reference standard covers the storage of liquid propane gas? - ✔✔NFPA
58
A service station is being built with one boiler 28 feet away from the meter that
uses natural gas; all other equipment is electric. What size K or L semi-rigid
copper tubing should be installed to supply 205 cu. ft. of gas per hour with an
inlet pressure less than 2 psi, pressure drop of 0.3 in. W.C. and a specific gravity
of 0.60? - ✔✔1 "
Maximum distance a gas shut-off valve can be installed from the equipment it
serves? - ✔✔6 feet
NFPA 54 9.6.4.1
Maximum distance off the ceiling of the room shall an indoor combustion air
opening be installed? - ✔✔12"
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, NFPA 54 9.3.2.3
What is the minimum required clearance for an unlisted pool heater on all sides
and rear? - ✔✔12"
NFPA 54 10.21.2(3)
Flanges used for gas piping shall have gaskets made of an approved material
designed to withstand temperatures, pressure and chemical constituents of the
gas. Which of the following gasket materials is not acceptable? - ✔✔Rubber
NFPA 54 5.6.11
When corrosive or flammable fumes or gases are present near appliances, a safe
disposal method shall be provided. All of the following are considered
flammable or corrosive EXCEPT?! - ✔✔Anhydrous Citric Acid
When a mechanical appliance is installed in an excavation deeper than 12",
what shall the excavation be lined with? - ✔✔Copper pan, concrete pit, or other
suitable material
NFPA 54 10.11.9
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