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DNV's Petition for Phast Version 8.4 as an Alternative Model for Calculating the Vapor-Gas Dispersion Exclusion Zone


PHMSA is publishing this notice, a draft letter of decision, and a draft environmental assessment (DEA) to solicit public comment on a petition to authorize the use of an alternate flammable vapor-gas dispersion model. At the conclusion of the 30-day comment period, PHMSA will review the comments received from this notice as part of its evaluation to grant or deny the petition.

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