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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 www.regulations.gov under docket PHMSA-2021-0041.

DOT is committed to ensuring that information is available in appropriate alternative formats to meet the requirements of persons who have a disability. If you require an alternative version of files provided on this page, please contact PHMSA-Accessibility@dot.gov.
Effective Date: Thursday, April 13, 2023
Issued Date: Thursday, April 13, 2023