Answers and Analysis
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Questions matching UMC Chapter 13
16 results
UMC 2003 1301.0, see also 1313.0
UMC 2006 1301.0, see also 1313.0
UMC 2009 1301.0, see also 1315.0
UMC 2012 1301.0, see also 1315.0
Topic: Regulation of LPG Systems
Does the installation of LPG tanks, underground piping, regulators, and meters fall within the authority and scope of the UMC, or are these facilities considered service piping and therefore the responsibility of the servicing LPG supplier?
Section 1313.0 (1315.0, 2009/2012) states, "Liquefied petroleum gas shall comply with NFPA 58, Liquefied Petroleum Gas Code."
UMC 2003 1303.5
UMC 2006 1303.5
UMC 2009 1303.5
UMC 2012 214
Topic: LPG Facilities
Do liquefied petroleum gas (LPG) facility appurtenances include LPG piping and shutoff valves serving an appliance?
No. LPG facilities as defined in Section 1303.5 consist of the LPG storage tanks, regulators and associated equipment. The piping, appliances, water heaters, and associated shutoff valves are not the facilities but are part of the fuel gas systems.
UMC 2003 1304.3.2
UMC 2006 1304.3.2
UMC 2009 1304.3.2
UMC 2012 1304..3.3
Topic: Test Gauges
Is a low-pressure gas test limited to a 10 pound test using a 20 pound gauge, or would a 26 pound test using a 52 pound gauge comply with code requirements?
A required 10 pound test mandates a gauge with minimum incrementations of 1/10 pound, while restricting the pressure range of the gauge to not greater than twice the pressure applied. Therefore, a required 10 pound test may be performed at any pressure (in excess of the minimum required pressure), provided the gauge incrementations do not exceed 1/10 pound and the test pressure applied is at least one-half of the pressure range of the gauge.
UMC 2003 1309.5.2.2
UMC 2006 1309.5.8.4(2)
UMC 2009 1309.5.8.4(2)
UMC 2012 1308.5.10.4
Topic: Use of Galvanized Fittings in Gas Piping System
Are galvanized fittings allowed in a gas piping system?
Yes. Section 1309.5.2.2 (2003) (1309.5.8.4(2), 2006/2009), (1308.5.10.4, 2012) allows for the use of galvanized pipe and, therefore, allows the use of galvanized fittings.
UMC 2003 1309.5.4
UMC 2006 1309.5.4
UMC 2009 1309.5.4
UMC 2012 1311.1.7
Topic: Alternate Methods of Construction
Would the installation of a plastic gas line under an ocean pier be a code violation?
No. Section 1309.5.4 (1311.1.7, 2012) states, "plastic pipe, tubing and fittings shall be used outside, underground only."
UMC 2003 1309.5.4
UMC 2006 1309.5.4
UMC 2009 1309.5.4
UMC 2012 1308.5.11.2
Topic: PE Gas Piping
Section 1309.5.4 recognizes PE as an approved material for distributing natural gas in exterior buried piping systems. The two acceptable methods for joining PE gas piping are by heat fusion or with an approved mechanical joint. Is the heat fusion application, either butt or socket, considered a welded joint?
No, a heat-fused joint on PE piping is not considered a welded joint. Fusion is the act or process of melting or the state of being melted or blended. This process is the coalition of components during a heated state. The term "welded joint or seam" as it is used in the UMC is applicable to metal only.
UMC 2003 1309.5.7(D)
UMC 2006 1309.5.7(D)
UMC 2009 1309.5.7(D)
UMC 2012 1308.5.9.3
Topic: Gas Piping - Teflon Tape
Is Teflon tape an approved pipe joint material for gas pipe installations?
Yes, listed Teflon tape is acceptable when carefully and correctly applied to male threads only, since it is insoluble in the presence of fuel gas.
UMC 2003 1309.7.5(A)(1)
UMC 2006 1309.7.5(A)(1)
UMC 2009 1309.7.5(A)(1)
UMC 2012 1309.7.5.1(1)
Topic: Piping Material for Gas Regulator Vents
1. When installing a gas regulator on a medium-pressure gas service, can the relief vent on the regulator be piped to the outside air with soft-copper refrigeration tubing?
2. Can the same tubing be used for step down (stage 1 and 2) regulators?
2. Can the same tubing be used for step down (stage 1 and 2) regulators?
1. Yes, if the requirements of Section 1309.5.2.3 (2003/2006/2009), 1309.5.2.3 (2012) are met.
2. Yes, same answer as above.
2. Yes, same answer as above.
UMC 2003 1311.2.4
UMC 2006 1311.2.5
UMC 2009 1311.2.5
UMC 2012 1311.2.5
Topic: Gas pipe Location
Is it permissible for concealed, unprotected gas piping with screwed joints to be installed in walls or floor/ceiling assemblies that are "framed and rocked" without the use of recesses, channels, or access panels? What about welded joints?
Yes. It is permissible for concealed, unprotected gas piping to be installed in walls or floor/ceiling assemblies that are framed and rocked. In addition, this would include welded joints as well as screwed joints.
UMC 2003 1311.2.6(A)
UMC 2006 1311.2.6(A)
UMC 2009 1312.2.6(A)
UMC 2012 1311.2.5
Topic: Hangers and Supports
Does gas piping installed in such a way as to be laying on and supported by trusses, joists, or other structural members, at least at intervals required by Table 13-3, require attaching to these structural supports with metal straps?
Yes. Section 1311.2.6(A) [1312.2.6(A), 2009] [1311.2.5, 2012] requires gas piping to be "adequately supported by metal straps or hooks at intervals not to exceed those shown in Table 13-3 (2003/2006/2009), T1311.2.5.1 (2012)."
All piping must be secured to prevent movement. Properly securing the piping ensures that a good-faith effort has been applied to prevent unintended lateral movement which might result in the piping being damaged or strained.
All piping must be secured to prevent movement. Properly securing the piping ensures that a good-faith effort has been applied to prevent unintended lateral movement which might result in the piping being damaged or strained.
UMC 2003 1311.3
UMC 2006 1311.3
UMC 2009 1312.3
UMC 2012 1311.3
Topic: Concealed Piping
Right and left couplings were installed for the fuel gas line, located in the crawl space.
1. Is the couplings location in the crawl space allowed by the UMC for service accessibility?
2. Is crawl space considered as a concealed space per Section 1311.3?
1. Is the couplings location in the crawl space allowed by the UMC for service accessibility?
2. Is crawl space considered as a concealed space per Section 1311.3?
1. Yes.
2. No. A crawl space is considered to be accessible, unless it meets the definition of concealed which is to hide or cover up. Most crawl spaces meet the definition of accessible, but there may be a case where the crawl space is not large enough for adequate access and is considered not accessible which could then be defined as a concealed space.
2. No. A crawl space is considered to be accessible, unless it meets the definition of concealed which is to hide or cover up. Most crawl spaces meet the definition of accessible, but there may be a case where the crawl space is not large enough for adequate access and is considered not accessible which could then be defined as a concealed space.
UMC 2003 1311.3.2
UMC 2006 1311.3.2
UMC 2009 1312.3.2
UMC 2012 1311.3.1(1)
Topic: Bushings in Gas Lines
Section 1311.3.2 (1312.3.2, 2009) states, in part that, "Bushings shall not be used in concealed locations." Would this include accessible attics and underfloor areas?
No. "Accessible locations in attics and underfloor locations," as described in the question, would not require removal of permanent construction to gain access to the piping and would, therefore, not be prohibited from the use of bushings in the piping system.
While the UMC does not define "concealed" as used in Section 1311.3.2 (1312.3.2, 2009), (1311.3.1(1), 2012), NFPA 54 does define it as it relates to gas piping as follows, "Gas piping, which, when in place in the finished building, would require removal of permanent construction to gain access to the piping."
While the UMC does not define "concealed" as used in Section 1311.3.2 (1312.3.2, 2009), (1311.3.1(1), 2012), NFPA 54 does define it as it relates to gas piping as follows, "Gas piping, which, when in place in the finished building, would require removal of permanent construction to gain access to the piping."
UMC 2003 1311.3.2
UMC 2006 1311.3.2
UMC 2009 1312.3.2
UMC 2012 1311.3.1(1)
Topic: Ansul Valves Installed with Unions
May a ground joint union used in connection with an Ansul valve be installed above a T-bar ceiling system?
No. An ansul valve installed above a T-bar ceiling is not exposed. The term "exposed" is not defined in the UMC, but is defined in Webster’s Dictionary as "open to view."
UMC 2003 1311.7.2
UMC 2006 1311.7.2
UMC 2009 1312.7.2
UMC 2012 1311.8.1
Topic: Capping Future Gas Connections
1. Is a future gas "stub-out" required to be provided with a shutoff valve and cap?
2. Is a capped outlet without a shutoff valve considered a completed gas system?
2. Is a capped outlet without a shutoff valve considered a completed gas system?
1. No
2. Yes
2. Yes
UMC 2003 1311.9.3
UMC 2006 1311.9.3
UMC 2009 1312.79.3
UMC 2012 1311.10.2
Topic: Main Supply Shutoff Valve
Does the shutoff valve installed on gas service piping (ahead of the meter) satisfy the intent of Section1311.9.3 (1312.9.3, 2009) (1311.10.2, 2012)?
Yes.
UMC 2003 1309.5.6
UMC 2006 1309.5.6
UMC 2009 1309.5.6
UMC 2012 1308.5.8
Topic: Protective Coating
When steel pipe is used for fuel gas piping on a roof top, does it need to be protected? If so, would painting the pipe give the proper coating?
Yes, all gas piping need to protected in an approved manner using coatings or wrappings. The AHJ has the authority to approve or disapprove the protective coating to be used. Steel piping used in outdoor environments, whether below ground or above ground is subject to corrosion. Some steel products have a greater resistance to corrosion than others. There are also many different exterior environments that could call for different levels of corrosion resistance. For example, an installation on a roof that is located near the beach may have air contacting the pipe that is more corrosive than in the desert. Some regions have significant snowfall and the piping would need to be protected to address snow.
There are many manufactures that have products that when applied to steel pipe resist corrosion. Local jurisdictions can decide what the appropriate level of corrosion resistance is required. If the gas pipe is to be painted to prevent a corrosive action, surface oils and dirt would need to be removed from the pipe prior to the pipe being primed and then painted.
There are many manufactures that have products that when applied to steel pipe resist corrosion. Local jurisdictions can decide what the appropriate level of corrosion resistance is required. If the gas pipe is to be painted to prevent a corrosive action, surface oils and dirt would need to be removed from the pipe prior to the pipe being primed and then painted.