ALOHA is the air hazard modeling program in the CAMEO software suite developed jointly by NOAA and the Environmental Protection Agency (EPA), and it runs on both Windows and Mac computers. Download ALOHA from the EPA CAMEO site.

Based on your information about a chemical release, ALOHA’s source strength models estimate how quickly the chemical will escape from a tank, puddle, or gas pipeline and form a hazardous gas cloud—and also how that release rate may change over time.

An ALOHA threat zone estimate displayed on a MARPLOT map.
An ALOHA threat zone estimate displayed on a MARPLOT map. The red, orange, and yellow zones indicate areas where specific Level of Concern thresholds were exceeded.

ALOHA can then model how that hazardous gas cloud will travel downwind—including both neutrally buoyant and heavy gas dispersion. Additionally, if the chemical is flammable, ALOHA also models pool fires, BLEVEs, vapor cloud explosions, jet fires, and flammable gas clouds (where flash fires might occur).

ALOHA produces a threat zone estimate, which shows the area where a particular hazard (such as toxicity or thermal radiation) is predicted to exceed a user-specified Level of Concern (LOC) at some time after the release begins.

The threat zone estimates are show on a grid in ALOHA, and they can be plotted on maps in MARPLOT, Esri’s ArcMap (using the ALOHA ArcMap Import Tool), and Google Maps and Google Earth (using ALOHA’s KML Export).

More Information about ALOHA

  • ALOHA Fact Sheet [PDF, 602 KB]: Learn more about program features by reading this ALOHA fact sheet.
  • ALOHA Examples [PDF, 2 MB]: Download a training document with three step-by-step fictional ALOHA example scenarios.
  • Ask Dr. ALOHA: Get to know ALOHA better by reading this series of informational articles that discuss key program features and walk through sample ALOHA scenarios.
  • ALOHA Development History: Read about the most significant changes made in each release of the ALOHA program.
  • Met Station Vendor List: Look though a list of vendors of portable meteorological stations designed to work with ALOHA and find out how to design a met station for ALOHA.
  • ALOHA Technical Resources: Review these documents if you are interested in developing a program or tool to work with ALOHA or if you want to learn about the equations that ALOHA uses.
  • CAMEO News Service: Join this email list on the EPA CAMEO site to receive news and other helpful information from the development team.
  • CAMEO Software Suite: Find out more about the four core programs—and several related programs—in the CAMEO software suite, which aids in hazardous material response and planning.

Questions: Contact us with questions, comments, or suggestions about ALOHA.