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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Approval of Phast v8.4 as an Alternate Model for Liquefied Natural Gas (LNG) Flammable Vapor-Gas Dispersion Exclusion Zones

On April 13, 2023, PHMSA approves DNV’s petition for Phast version 8.4 as an alternative model for calculating the flammable vapor dispersion exclusion zones under 49 C.F.R. § 193.2059(a). The Final Environmental Assessment discusses the analysis of the validation results. Other documentations related to this petition can be found in under docket PHMSA-2021-0041.

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Effective Date: Thursday, April 13, 2023
Issued Date: Thursday, April 13, 2023