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United States Department of Transportation United States Department of Transportation

AC 450.139-1 - Toxic Hazards

Document Information

Number
450.139-1
Title
Toxic Hazards
Status
Active
Date issued
2024-07-08
Office of Primary Responsibility
AST-1, Office of Commercial Space Transportation
Description

This AC provides guidance for an operator conducting a licensed launch or reentry under 14 CFR part 450. In accordance with §§ 450.139 and 450.187, as applicable, an operator that uses toxic propellants or other toxic chemicals must conduct a toxic release hazard analysis (TRHA), manage the risk of casualties that could arise from
exposure to toxic release through toxic containment or a toxic risk assessment, and establish flight commit criteria and ground hazard controls, as applicable, for any necessary evacuation of the public from a toxic hazard area. This current version of this AC discusses only how to identify whether there are toxic materials which is sufficient for demonstrating non-applicability with §§ 450.139 and 450.187 or using a Federal entity to perform a TRHA. A future version will include additional information on performing a TRHA.

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