[Code of Federal Regulations] [Title 24, Volume 1] [Revised as of April 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 24CFR51.203] [Page 388] TITLE 24--HOUSING AND URBAN DEVELOPMENT PART 51_ENVIRONMENTAL CRITERIA AND STANDARDS--Table of Contents Subpart C_Siting of HUD-Assisted Projects Near Hazardous Operations Handling Conventional Fuels or Chemicals of an Explosive or Flammable Nature Sec. 51.203 Safety standards. The following standards shall be used in determining the acceptable separation distance of a proposed HUD-assisted project from a hazard: (a) Thermal Radiation Safety Standard. Projects shall be located so that: (1) The allowable thermal radiation flux level at the building shall not exceed 10,000 BTU/sq. ft. per hr.; (2) The allowable thermal radiation flux level for outdoor, unprotected facilities or areas of congregation shall not exceed 450 BTU/sq. ft. per hour. (b) Blast Overpressure Safety Standard. Projects shall be located so that the maximum allowable blast overpressure at both buildings and outdoor, unprotected facilities or areas shall not exceed 0.5 psi. (c) If a hazardous substance constitutes both a thermal radiation and blast overpressure hazard, the ASD for each hazard shall be calculated, and the larger of the two ASDs shall be used to determine compliance with this subpart. (d) Background information on the standards and the logarithmic thermal radiation and blast overpressure charts that provide assistance in determining acceptable separation distances are contained in appendix II to this subpart C. [49 FR 5103, Feb. 10, 1984, as amended at 61 FR 13334, Mar. 26, 1996]