248 CMR, § 5.05 - Modifications to Chapter 5, Gas Piping System Design, Materials, and Components

(1) Delete sub-section 5.1.1 and replace with the following:

5.1.1 Installation of Piping Systems over Five Million BTU/hr. In addition to the permit requirements of 248 CMR 3.00: General Provisions Governing the Conduct of Plumbing and Gas Fitting Work Performed in the Commonwealth, for gas installations of over 5,000,000 BTU/hr the following is required:

(a) All piping systems over 5,000,000 BTU/hr shall be designed by a Massachusetts registered professional engineer. The design shall assure that the piping installation, including pipe sizing, dimension, and other aspects, meet the requirements for proper functioning, safety, and this code. The installer must submit drawings to the Inspector stamped by the engineer reflecting this design prior to being issued a permit. The installer shall also submit with the drawings a written statement from the serving gas supplier that it is able to provide fuel meeting the volume, pressure, and maximum gas demand required by the drawings as well as that required by any existing gas systems.

(b) Once the installation is complete but prior to final inspection, the installer must provide the Inspector with a written certification by a Massachusetts registered professional engineer that the installation complies with the stamped drawings and specifications. The Inspector shall not be responsible for approving or inspecting design specifications, but must ensure the installation adheres to the provisions of 248 CMR 5.00.

(2) Add a new sub-section 5.1.3 as follows:

5.1.3 Dual Fuels Installed in Buildings and Structures. When Utility/Natural Gas and Undiluted Liquefied Petroleum Gas (Propane Gas) systems are installed within the same building or structure, the following additional conditions must be satisfied as well as those conditions required for each individual fuel system:

(a) Written permission for the installation must be obtained by local fire officials and applicable utilities.

(b) The natural gas and propane gas piping systems shall be labeled in the following manner:

1.at a minimum of every ten feet;

2.at all changes of direction;

3.on each side of a penetration through a partition, wall or ceiling;

4.at every gas shut off valve;

5.for natural gas (color-coded yellow) and propane gas (color coded light green), the labels shall be;

a.black lettering indicating the type of gas within the piping system;

b.the letters shall be sized equal to a minimum of the pipe diameter. However, for piping with a diameter exceeding two inches, said lettering does not need to be larger than two inches.

(3) Add a new sub-section 5.4.2.3 as follows:

5.4.2.3 Diversity Factor for Domestic Ranges. Diversity factor is an important factor determining the correct gas piping size to be used for supplying domestic ranges in multiple family dwellings; it applies to domestic ranges only and shall not apply to any other gas appliances.

TABLE 5.4.2.3

Multi-family Dwellings Diversity Factor in Percent of Total Load for Domestic Gas Ranges with connected Load Ratings of 63,000 Btu/hr. or more per Range

No. of Ranges	Demand cubic ft/hour	Percent of Ratings	No. of Ranges	Demand cubic ft/hour	Percent of Ratings
1	63	100	13	270	33
2	107	85	14	283	32
3	132	70	15	293	31
4	151	60	16	312	31
5	173	55	17	33	30
6	189	50	18	340	30
7	198	50	19	346	29
8	212	42	20	353	28
9	225	39	21	358	27
10	233	38	22	374	27
11	243	37	23	390	27
12	257	35	24 & Over	408	27

(4) Replace sub-section 5.5.1 with the following:

5.5.1 Maximum Design Operating Pressure.

(a) General Rules. See 248 CMR 4.03(1)(b)

(b) Elevated Pressure.

1.All elevated pressure systems shall be designed by a Massachusetts registered professional engineer. The design shall assure that the piping installation, including pipe sizing, dimension, and other aspects, meet the requirements for proper functioning, safety, and this code. The installer must submit drawings to the Inspector stamped by the engineer reflecting this design prior to being issued a permit. The installer shall also submit with the drawings a written statement from the serving gas supplier that it is able to provide fuel meeting the volume, pressure, and maximum gas demand required by the drawings as well as that required by any existing gas systems. The provisions of this paragraph shall not be in effect until July 1, 2015. Prior to July 1, 2015, elevated pressure systems shall be subject to the special permission requirements of 248 CMR 3.04(3).

2.Once the installation is complete but prior to final inspection, the installer must provide the Inspector with a written certification by a Massachusetts registered professional engineer that the installation complies with the stamped drawings and specifications. The Inspector shall not be responsible for approving or inspecting design specifications, but must ensure the installation adheres to the provisions of 248 CMR 5.00.

3.When the maximum design operating pressure exceeds five PSIG, all piping shall be welded in accordance with subsection 5.6.2.2.1.

4.Elevated pressure piping shall be labeled in the following manner:

a.At a minimum of every ten feet;

b.At all changes of direction;

c.On each side of a penetration through a partition, wall or ceiling;

d.At every gas shutoff valve; and

e.The labels shall be yellow with black lettering that:

i.indicates the type of gas and the pressure contained within the piping system,and

ii.the letters shall be sized equal to a minimum of the pipe diameter. However,for piping with a diameter exceeding two inches, said lettering does not need to be larger than two inches; and

iii.for elevated dual fuel applications, labels for propane systems shall be color-coded light green.

f.Labeling shall not be required for elevated pressure piping that is between the first and second stage regulator in a liquefied petroleum gas installation.

5. Exceptions. The requirements of a professional engineer for elevated pressure installations shall not be required for:

a.installations of propane gas piping systems utilizing elevated pressure that are located between the first and second stage regulator when the second stage regulator is located on the exterior of a building; and

b.installations of gas piping between a meter and a regulator not installed/supplied by a gas company when the gas piping from the meter to the regulator does not exceed ten feet.

(5) Add a new sub-section 5.5.1.1 as follows:

5.5.1.1 Gas Pressure Boosters. Gas pressure boosters may be installed in that portion of the gas piping system extending from the outlet of the meter set assembly to the inlet of the equipment requiring elevated or increased pressure when the following conditions have been satisfied:

(a) All gas pressure boosters must meet Product-acceptance requirements;

(b) the serving gas supplier has provided written authorization;

(c) If not part of the booster, the equipment served by the booster shall be equipped with a manual re-set low gas pressure switch and a check valve upstream of the booster. By-passes for pressure boosters shall include a manual shut off and a check valve;

(d) A pressure regulator shall be provided to maintain a constant outlet pressure and be installed immediately downstream of the booster except when the pressure booster is equipped with an integral pressure regulator;

(e) Gas pressure boosters shall be installed on a firm foundation or surface capable of supporting the imposed load, and the booster shall be kept free of vibration by the installation of vibration arrestors; and

(f) Gas pressure boosters shall be located in well ventilated spaces and be readily accessible for examination, maintenance or replacement.

(6) Add a new sub-section 5.6.2.2.1 with the following:

5.6.2.2.1 Welding of Steel and Wrought Iron Pipe.

(a) Welding shall not be construed as the practice of gas-fitting, however, a licensed plumber or gas fitter may not utilize welded pipes and fittings unless they conform to the specifications cited in subsections 5.6.2.2 and A.5.5.1 (1).

(b) Gas piping systems with pressures under or equal to 70 P.S.I.G shall only be permitted to utilize welded pipes and fittings when:

1.The inspector has performed a visual inspection as to the quality of the weld; and

2.The test pressure used during an Inspection complies with the following:

a.Systems with a maximum operating pressure of ten P.S.I.G. or less, shall be tested to a minimum of three P.S.I.G. or ten times the operating pressure, whichever is greater.

b.Systems with an operating pressure greater than ten P.S.I.G. and less than or equal to 70 P.S.I.G. shall be tested at 100 P.S.I.G.

c.The test duration shall be one hour for every 100 feet of pipe, or fraction thereof.

The minimum test duration shall be one hour and the maximum test duration shall be 24 hours, irrespective of system design. (c) Gas piping systems with pressures over 70 P.S.I.G. may only utilize welded pipes and fittings when:

1.All welds are of full penetration; and

2.The welds are subjected to the following tests:

a.All welds are subjected to a 100% X-ray or 100% Ultrasonic Examination (UT) test unless they are socket welded;

b.All socket welded type joints must be subjected to a magnetic particle test or other non-destructive test;

c.The gas piping system shall be pressure tested to a minimum of 1.25 times the gas piping systems working pressure. However, the test duration must be a minimum of one hour and the test must be witnessed by the Inspector; and,

d.Any testing company or field agent that provides a (UT) field examination must meet the requirements of 248 CMR 3.04(6). A copy of the testing certification shall be submitted to the Inspector.

3.Repairs that are made to welded joints that fail the X-Ray or (UT) test shall be re-tested and re-certified. For future reference; the failed welded joint that is re-tested shall be identified by stenciling 1/2 inch high white lettering at the weld location the date of the re-test.

4.The Inspector shall require an affidavit signed by the individual who performed the X-ray or (UT) examination for the testing agency. The affidavit shall state that all welds meet the requirements of the applicable specifications and tests.

(7) Add a new sub-section 5.6.2.7 as follows:

5.6.2.7 Galvanized. Galvanized pipe shall not be used.

(8) Replace sub-section 5.6.3.4 with the following:

5.6.3.4 Corrugated Stainless Steel.

(a) CSST Fittings. All fittings and accessories used in the installation of CSST piping systems shall be approved by the CSST manufacturer for use with their system and shall only be installed by licensees who have completed manufacturer training/certification acceptable to the Board.

(b) CSST Concealed Fittings.

1.Where gas piping is to be concealed:

a.connections shall only be made with CSST fittings listed for use in concealed spaces; and

b.connections shall be produced by the manufacturer of the CSST piping system.

2.Malleable fittings shall be permitted in concealed locations when used in combination with CSST fittings.

3.For each malleable fitting there shall only be a single CSST connection.

(c) Repairs to Concealed CSST Piping.

1.Repairs required in a CSST system which is concealed, or otherwise not readily accessible, shall be repaired with a fitting listed for the CSST system being used.

2.Installation of an access panel shall be required at the repair site.

(d) Interior Meter Connections. Interior meter connections may be directly connected to the CSST system as long as the meter is securely affixed to the building, and the CSST is secured to the building structure when 24 inches or more of tubing is exposed.

(e) Exterior Meter Connections.

1.No CSST shall be connected to an exterior meter.

2.The tubing shall terminate at the foundation wall with a termination fitting, and the meter shall be rigidly connected with steel piping to the building structure.

(f) Sleeved Gas CSST.

1.CSST shall be sleeved when passing through a metal or concrete deck to protect the integrity of the tubing. Licensees should be aware that the tubing may be required to be fire stopped/rated per 780 CMR: Massachusetts Amendments to the International Building Code 2009. If applicable, this requirement will be regulated/ enforced by the Building Inspector, not the Inspector as defined in 248 CMR 3.01: Definitions.

2.The sleeve shall be Schedule 40 black or galvanized pipe and shall extend a minimum six inches from the top of the finished floor and the underside of the deck.

(g) Only manifolds for CSST systems supplied and listed by the CSST manufacturer may be concealed.

1.Assembled manifolds shall be installed in an accessible location.

2.Assembled manifold is a piping combination made up of close nipples and malleable tees.

(h) Fireplace Log Installations.

1.CSST shall terminate with a termination fitting at the entrance to the masonry fire box.

2.The workmanship shall be performed and completed in such a manner so that the termination will not be exposed to any adverse effects.

(i) Fixed Appliance Connection Using CSST. CSST may be directly connected to a fixed appliance when the following conditions are met.

1.The tubing is securely attached to the building structure or other means of solid support.

2.Tubing shall not run exposed for a distance greater than or equal to 30 inches without being physically attached to the building structure or other means of solid support.

3.CSST terminates with a proper fitting and gas cock.

(j) CSST Used Underground. .

1.When in contact with the earth or other material that could corrode the piping, the CSST shall be installed within a sleeve designed to withstand the superimposed loads.

2.Except for pre-engineered sleeves that are Product-accepted by the Board, the sleeve shall allow free movement of the CSST.

3.All sleeve ends shall be sealed liquid tight.

4.An acceptable tape marking system shall be in place no more than six inches from the top of the grade indicating that a gas line is below.

5.The minimum depth for buried gas piping as describe herein is 18 inches from the top of grade.

(k) CSST Used as an Appliance Connection. CSST shall not be used as a flexible appliance connector downstream of the appliance shutoff device.

(l) Sizing CSST Systems. CSST systems shall be sized and installed with a maximum 14 inch water column (0.5 P.S.I.G.) gas pressure.

(m) CSST Installation and Modifications. Installation of CSST in the Commonwealth of Massachusetts shall be in strict compliance with the manufacturer's instructions and the Massachusetts State Plumbing and Gas Code 248 CMR 3.00: General Provisions Governing the Conduct of Plumbing and Gas Fitting Work Performed in the Commonwealth through 7.00: Large Gas Utilization Equipment.

(n) Testing Requirements for CSST Systems.

1.Before any piping is covered, when CSST piping systems are installed in new construction or remodeling, the system shall be tested as part of the Inspection as prescribed under Section 7.1 as modified under 248 CMR 5.05.

2.Before piping is connected to any appliance the licensed plumber or gas fitter shall do a second test of the system.

3.A tag shall be:

a.affixed to the meter or service manifold acknowledging this test; and

b.signed and dated by the licensed plumber or gas fitter.

(o) Liquid Leak Detector. No corrosive liquids shall be used in the testing of the CSST system. Some household soaps and detergents may be corrosive to gas and plumbing products.

(p) Exposed CSST Tubing. When CSST is installed outdoors or is subject to corrosive chemicals, exposed stainless CSST tubing (where the jacket has been removed) shall be recovered with tape as specified by the CSST manufacturer. Said re-covering of CSST shall occur following the testing.

(q) CSST Piping Installed on Roofs. CSST shall be installed for roof top equipment only when it is supported by one of the following methods:

1.The CSST tubing with a UV stabilized jacket is supported the full length of the CSST run.

a.The tubing shall be affixed to a wooden plank or a steel channel that is securely attached by an appropriate method every six feet to the roof structure.

b.The tubing shall be attached directly to the support every six feet.

2.The CSST tubing is installed within a metal or plastic conduit that is securely attached by an appropriate method every six feet to the roof structure. Where the piping system requires a tee to be installed within the line, the sleeve shall terminate no more than 12 inches from the tee on both runs and the branch line.

3.For CSST tubing having sizes of 1.5 and two inches and having a UV stabilized jacket, the following requirements shall be satisfied:

a.the CSST shall be supported on blocks which are spaced not more than 48 inches apart.

b.The blocks shall be constructed of materials appropriate for outdoor conditions and shall be securely attached by an appropriate method to the roof structure, and:

c.The method used to attach the CSST to the block shall not damage the plastic coating.

d.The maximum length of tubing not supported by any method listed shall not exceed 30 inches when connected to a gas fired roof top unit or similar gas equipment.

(9) Replace subsection 5.6.8.4(1) with the following:

Pipe and Fittings in excess of four inches in diameter shall be welded.

(10) Amend subsection 5.6.8.4(2) by deleting "or cast iron"

(11) Replace subsection 5.6.8.4(5) with the following:

Cast iron is only permitted for flanges, valves, strainers, and filters.

(12) Add a new subsection 5.6.8.5 as follows:

5.6.8.5 Other Fittings. Notwithstanding the provisions of this section, metallic piping joints and fittings which do not otherwise meet the requirements of this section may be utilized if approved by the Board or otherwise have met the product acceptance requirements of 248 CMR 3.04(1): Board Required Product-acceptance.

(13) Add a new subsection 5.7.6 as follows:

5.7.6 Limitation. The provisions of this section shall only apply to premises owned gas meters, which are comprised of a secondary meter and meter assembly installed on the downstream portion of the gas piping system of a serving gas supplier's meter.

(14) Replace section 5.12 with the following:

5.12 Manual Shutoff Valves.

Acceptable Shutoff Devices: Gas Cocks and Ball Valves installed for use shall be listed. The Valves shall:

(a) Have clearly indicated open and closed positions and rigidly secured stops to limit both extremes of rotation;

(b) shall be marked in a conspicuous place with the manufacturer's name or registered trademark; and

(c) Where in contact with material or atmosphere exterting a corrosive action, a corrosion resistant handle shall be utilized.

Notes

248 CMR, § 5.05

Amended by Mass Register Issue 1275, eff. 12/5/2014.