DOB Clarifies Testing Requirements for Gas Piping Alterations
By Frank Fortino
On January 18, 2017, the New York City Department of Buildings (DOB) issued Buildings Bulletin 2017-001 to clarify testing requirements when altering fuel gas piping systems. While the New York City Fuel Gas Code (FGC) addresses required inspections and testing, the new bulletin provides a detailed explanation of DOB requirements.
NYC Fuel Gas Code
Sections 107.2 and 107.3 of the FGC describe the inspections and testing required before placing gas piping into service, and Section 406.1 requires testing gas piping systems as a complete unit. The FGC also requires a complete unit test when adding a new branch to an existing system, which was previously tested and placed in service. However, the code allows testing less than the entire gas piping system when affected portions can be isolated from the unaltered piping. Finally, any additions, alterations, or repairs require testing of the affected piping.
Section 409.3 requires separate shutoff valves for each tenant space in multi-tenant buildings with a single gas meter. When altering the gas piping within a single tenant space downstream of the shutoff valve, testing may be isolated to the affected tenant space; more extensive testing is required in buildings without individual shutoff valves.
The technical bulletin uses the same terms and definitions as the FGC, but offers additional information. For instance, a branch is defined as “a section of gas piping downstream from a riser, leading to appliances or equipment on no more than two consecutive floors.” This definition elaborates on FGC Section 404.5, which states, “Branches shall be taken off the riser with not less than a two-elbow swing.”
In addition, the bulletin expands on the term isolated, providing both explanation and illustration of acceptable methods for isolating a specific portion of the gas piping system.
- Double Block & Bleed Assembly. Plumbers may isolate the affected piping system with “a double block consisting of two valves installed in series with an intermediate telltale/bleed valve.”
- Cap Isolation. Another isolation method involves “disconnecting the new and altered piping from the existing piping and installing a temporary nipple/coupling and cap.”
Following successful pressure testing of the affected piping, the above-described isolation fittings are removed. The altered piping is reconnected to the existing system, and the new connection will be tested for leaks, per FGC Section 406.6.3.
Plumbers who perform this work need to familiarize themselves with both testing requirements and accepted isolation methods. Failure to comply with this bulletin can delay signoff and incur additional costs. They also need to account for the additional time and materials required for compliance. The last thing anyone wants is to have a DOB inspector review the finished work and demand a costly rebuild.
If you have any questions, please contact the Plumbing Division of Metropolis Group at 212.233.6344.