The 2000 uniform Plumbing code had this to say about ground joint unions:
2017 California Mechanical Code has this to say (or not) about ground joint unions:
Connections. Where gas piping is to be concealed, connections shall be of the following type:
(1) Pipe fittings such as elbows, tees, couplings, and right/left nipple/couplings.
(2) Joining tubing by brazing (see Section 1208.5.8.2).
(3) Fittings listed for use in concealed spaces or that have been demonstrated to sustain, without leakage, forces due to temperature expansion or contraction, vibration, or fatigue based on their geographic location, application, or operation.
(4) Where necessary to insert fittings in gas pipe that has been installed in a concealed location, the pipe shall be reconnected by welding, flanges, or the use of a right/left nipple/coupling.
2017 California Mechanical Code definition:
Concealed Spaces. That portion(s) of a building behind walls, over suspended ceilings, in pipe chases, attics, and elsewhere whose size might normally range from 13⁄4 inch (44 mm) stud spaces to 8 foot (2438 mm) interstitial truss spaces and that might contain combustible materials such as building structural members, thermal, electrical insulation, or both, and ducting. Such spaces have sometimes been used as HVAC plenum chambers.
The contention is that a ground joint union is not allowed in an attic next to a furnace because the Mechanical Code includes attics in the definition of a concealed space. What do you think about that?
2017 California Mechanical Code has this to say (or not) about ground joint unions:
Connections. Where gas piping is to be concealed, connections shall be of the following type:
(1) Pipe fittings such as elbows, tees, couplings, and right/left nipple/couplings.
(2) Joining tubing by brazing (see Section 1208.5.8.2).
(3) Fittings listed for use in concealed spaces or that have been demonstrated to sustain, without leakage, forces due to temperature expansion or contraction, vibration, or fatigue based on their geographic location, application, or operation.
(4) Where necessary to insert fittings in gas pipe that has been installed in a concealed location, the pipe shall be reconnected by welding, flanges, or the use of a right/left nipple/coupling.
2017 California Mechanical Code definition:
Concealed Spaces. That portion(s) of a building behind walls, over suspended ceilings, in pipe chases, attics, and elsewhere whose size might normally range from 13⁄4 inch (44 mm) stud spaces to 8 foot (2438 mm) interstitial truss spaces and that might contain combustible materials such as building structural members, thermal, electrical insulation, or both, and ducting. Such spaces have sometimes been used as HVAC plenum chambers.
The contention is that a ground joint union is not allowed in an attic next to a furnace because the Mechanical Code includes attics in the definition of a concealed space. What do you think about that?
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