Cargo-Specific Air Dispersion and Impact Zone Analysis After Accidental Release of Hazardous Materials

Impacts of a hazardous material release during transport depend on the characteristics of the cargo, incident location, incident time, weather conditions (i.e., wind direction and speed), and land use. The objectives of this research were to characterize the dispersion characteristics of two hazardous materials (ammonia and hydrogen fluoride) with the meteorological parameters, land use, and cargo characteristics. The magnitudes of the impact zones were compared in relation to atmospheric stability and exposure levels. Impact zones were estimated by Areal Locations of Hazardous Atmospheres (ALOHA) software and imported to ArcGIS. The threshold exposure levels were defined according to the level of concern (LOC) concentrations for each hazardous material. Analyses were conducted for a hazmat release of 2 tons and wind speed of 5 mph. For ammonia, the areas impacted by exposure levels over 1100 ppm were limited to a distance of less than 0.3 miles directly downwind from the original release location under unstable atmospheric conditions, which favor high vertical mixing and rapid dilution, and extended further downwind to distances between 0.5 and 0.7 miles under stable atmospheric conditions. In contrast, for hydrogen fluoride the impact zone extended between 0.6 and 0.9 miles directly downwind from the original release location under unstable conditions, and reached approximately 2.0 miles directly downwind from the incident location under stable atmospheric conditions. The multilevel analysis of impacts after hazardous material releases during transport (i.e., type of material, geographical data, dispersion profile, meteorological information) can be used for implementing appropriate response and mitigation measures for hazardous.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AT040 Transportation of Hazardous Materials.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Inanloo, Bahareh
  • Tansel, Berrin
  • Jin, Xia
  • Bernardo Bricker, Anna
• Conference:
  • Transportation Research Board 93rd Annual Meeting
  • Location: Washington DC
  • Date: 2014-1-12 to 2014-1-16
• Date: 2014

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 15p
• Monograph Title: TRB 93rd Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Air quality; Ammonia; Disasters and emergency operations; Dispersions (Chemistry); Environmental impacts; Geographic information systems; Hazardous chemicals; Health hazards; Hydrogen inorganic compounds; Spills (Pollution)
• Uncontrolled Terms: Exposure (Pollutants)
• Subject Areas: Data and Information Technology; Environment; Freight Transportation; Planning and Forecasting; Security and Emergencies; I15: Environment; I72: Traffic and Transport Planning;

Filing Info

• Accession Number: 01515164
• Record Type: Publication
• Report/Paper Numbers: 14-0519
• Files: TRIS, TRB, ATRI
• Created Date: Feb 21 2014 3:18PM