ASD Calculator

Acceptable Separation Distance (ASD) Electronic Assessment Tool

The Environmental Planning Division (EPD) has developed an electronic-based assessment tool that calculates the Acceptable Separation Distance (ASD) from stationary hazards. The ASD is the distance from above ground stationary containerized hazards of an explosive or fire prone nature, to where a HUD assisted project can be located. The ASD is consistent with the Department's standards of blast overpressure (0.5 psi-buildings) and thermal radiation (450 BTU/ft2 - hr - people and 10,000 BTU/ft2 - hr - buildings). Calculation of the ASD is the first step to assess site suitability for proposed HUD-assisted projects near stationary hazards. Additional guidance on ASDs is available in the Department's guidebook "Siting of HUD- Assisted Projects Near Hazardous Facilities" and the regulation 24 CFR Part 51, Subpart C, Sitting of HUD-Assisted Projects Near Hazardous Operations Handling Conventional Fuels or Chemicals of an Explosive or Flammable Nature.

Note: Tool tips, containing field specific information, have been added in this tool and may be accessed by hovering over the ASD result fields with the mouse.

Acceptable Separation Distance Assessment Tool

Is the container above ground?  
Is the container under pressure?  
Does the container hold a cryogenic liquified gas?  
Is the container diked?  
What is the volume (gal) of the container?
What is the Diked Area Length (ft)?
What is the Diked Area Width (ft)?
Diked Area (sqft)
ASD for Blast Over Pressure (ASDBOP)
ASD for Thermal Radiation for People (ASDPPU)
ASD for Thermal Radiation for Buildings (ASDBPU)
ASD for Thermal Radiation for People (ASDPNPD)
ASD for Thermal Radiation for Buildings (ASDBNPD)

For mitigation options, please click on the following link: Mitigation Options

Providing Feedback & Corrections

After using the ASD Assessment Tool following the directions in this User Guide, users are encouraged to provide feedback on how the ASD Assessment Tool may be improved. Users are also encouraged to send comments or corrections for the improvement of the tool.

Please send comments or other input using Ask A Question. Enter "Environmental Review" in the "My question is related to" field.


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