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The Ask Dr. ALOHA articles are brief, informational articles designed to help you understand ALOHA better. Some of the articles are in-depth discussions of key topics (such as Levels of Concern), while other articles are short stories that walk you through using ALOHA in a particular scenario. We will continue to post new articles, so make sure to check this page periodically to see if there are any new articles of interest. If you would like to suggest a topic for an Ask Dr. ALOHA article, please send an email to the CAMEO Specialist.

Levels of Concern (LOCs)
  • Choosing Toxic Levels of Concern: This article contains an overview of toxic LOCs (including AEGLs, ERPGs, and PACs), a discussion on how to choose toxic LOCs in ALOHA, and some suggestions about when you should use LOCs other than ALOHA's standard values.
  • Working with Toxic and Odor Thresholds: This article describes a scenario where a responder needs to assess a chemical release using both toxic and odor thresholds as LOCs in order to evaluate the threat posed to the public.
Concentration Graphs
  • Working with the Concentration Graph: This article discusses exposure duration and how to use the concentration graph. The concentration graph shows indoor and outdoor concentrations of a chemical in the air at a specific location for one hour after the start of a chemical release.
Regulatory Planning Using ALOHA and CAMEO Data Manager

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

Last updated Tuesday, December 22, 2020 10:30pm PST