In response to concerns voiced by industry trade groups, the Department of Transportation’s Pipeline and Hazardous Materials Safety Administration said Tuesday it was delaying “indefinitely” a portion of changes to natural gas and oil pipeline inspection procedures that the agency proposed earlier this year.

PHMSA published a final rule in March amending the pipeline safety regulations to make miscellaneous changes that updated and clarified certain regulatory requirements (80 FR 12762). The amendments addressed subject matter areas including the performance of post-construction inspections; Type B onshore gas gathering line leak surveys; qualifying plastic pipe joiners; ethanol regulation; pipe transportation; offshore pipeline condition report filing; pressure reduction calculations for hazardous liquid pipeline anomalies, and components fabricated by welding.

But in a final rule released Wednesday, PHMSA delayed indefinitely the March 11 amendment revising 49 CFR 192.305, which specified that pipeline operators “must not use operator personnel to perform a required inspection if the operator personnel also performed the construction task that required inspection.” The American Public Gas Association (APGA) subsequently asked for clarification or reconsideration of the rule, saying it had the potential to impose significant costs on publicly-owned distribution systems with little or no corresponding safety benefit.

“According to APGA, 585 municipal gas utilities have 5 or fewer employees,” PHMSA said. “The APGA went on to say that prohibiting small utilities from having their own employees inspect pipeline construction work performed by employees of the municipal utility would significantly increase the costs for those utilities” by forcing them to hire third party inspectors.

In response, the National Association of Pipeline Safety Representatives (NAPSR) asked for a delay in the effective date of the final rule, saying that it would allow “contractor personnel to inspect the work performed by their own company,” which would create an inherent conflict of interest and defeat the intended safety benefits of the rule.

“Upon further examination of the impacts of this amendment, in particular the issues raised by the petitioners, PHMSA believes that further examination and analysis of this safety issue is warranted prior to this change going into effect,” PHMSA said.

Other amendments contained in the March final rule still go into effect on Thursday (Oct. 1), PHMSA said.