Lawrence Livermore National Laboratory

For toxic industrial chemicals, NARAC products show predicted areas where:

  • Near-term health effects may be experienced (calculated using the peak air concentration experienced during any 15-minute period)
  • Isolation and protective actions may be warranted, including restricted entry, evacuation, and/or sheltering
  • Use of personal protective equipment by emergency workers is recommended
  • Explosions may occur due to chemical concentration levels
  • Surface contamination may be present

Public exposure guidelines for health effects are based on protective action levels derived from (in the following order of priority):

  1. AEGLs: 60-minute EPA Acute Emergency Guideline Levels
  2. ERPGs: AIHA Emergency Response Planning Guidelines
  3. TEELs: DOE Temporary Emergency Exposure Limits

Exposure calculations assume that individuals remain outdoors in the same location throughout the plume passage.