ALOHA is the hazard modeling program for the CAMEO software suite, which is used widely to plan for and respond to chemical emergencies. Learn more about the CAMEO software suite.
ALOHA allows you to enter details about a real or potential chemical release, and then it will generate threat zone estimates for various types of hazards. ALOHA can model toxic gas clouds, flammable gas clouds, BLEVEs (Boiling Liquid Expanding Vapor Explosions), jet fires, pool fires, and vapor cloud explosions. The threat zone estimates are shown on a grid in ALOHA, and they can also be plotted on maps in MARPLOT, Esri's ArcMap, Google Earth, and Google Maps. The red threat zone represents the worst hazard level, and the orange and yellow threat zones represent areas of decreasing hazard.
- Download ALOHA for Windows (Version 5.4.6, Feb 2016, 7.22 MB EXE)
- Download ALOHA for Mac (Version 5.4.6, Feb 2016, 9.14 MB DMG); additional Mac instructions
The Windows version can be run on Windows 7, Windows 8, Windows 8.1, and Windows 10 operating systems. The Macintosh version can be run on Mountain Lion (10.8), Mavericks (10.9), Yosemite (10.10), and El Capitan (10.11) operating systems. Operating systems not listed here have not been tested and are not supported.
If you already have an older version of ALOHA: It is best to install the new ALOHA application in the same folder as your previous version. This will replace the old application with the new one, while still maintaining all of your settings. Any chemical information that you have added to the chemical library will not be saved and you will need to re-enter that information.
Learning More About ALOHA
ALOHA's help topics include an example problem that you can work through to familiarize yourself with the program. You can also download the ALOHA Examples (PDF), which has three additional step-by-step fictional example scenarios.(53pp, 2 MB, About PDF)
For additional information on using ALOHA (such as FAQs, a Level of Concern guide, tools for importing threat zones into Esri's ArcMap, and the Ask. Dr. ALOHA articles), see the ALOHA pages on the NOAA Office of Response and Restoration site.
What's New in ALOHA Version 5.4.6?
- Updated chemical library with new Levels of Concern (AEGLs, ERPGs, and PACs).
- Added CAS number (a chemical identification number) to the Text Summary screen.
- Fixed a typo in the source code for the Chamberlain equation, where the "CR" should be a multiplier in the final term of the equation (not an exponent). This could have an impact on some jet fire scenarios.
- Revised helps.
- Made additional minor changes and bug fixes.
You can report software bugs or obtain additional assistance by emailing the RMP Reporting Center (RMPRC@epacdx.net), or by calling the CAMEO help desk at (703) 227-7650 on weekdays from 8 AM to 4:30 PM, Eastern Time.