Ammonia health risk assessment and management

The National Advisory Committee on Acute Exposure Guideline Levels (NAC AEGL) decided to propose AEGL values for ammonia, which are lower than RAM TRAC recommendations. The values are generally too low by a factor of approximately 4.5, producing Emergency Planning Zone areas generally 20 times greater than necessary around facilities exceeding threshold quantities of ammonia on-site. The technical bases for concern about AEGL-2 and AEGL-3 values derived by the committee are summarized and some recommendations are made.