Lawrence Livermore National Laboratory

Hazardous Material Property Databases

NARAC maintains extensive databases of hazardous material properties supplemented by source term models which define other release characteristics needed in plume modeling. Examples of hazardous material property data include:

  • Radionuclides: decay rates and decay chain branching fractions
  • Toxic industrial chemicals and materials: physical and chemical properties for over 2500 chemicals
  • Chemical warfare agents: physical and chemical properties
  • Biological agents (live agents and toxins): viability information and environmental degradation rates drawn from multiple government sources

Protective Actions Guide and Health Effects Level Databases

Dose-response models and risk factors are used to calculate human exposures and are combined with population data to estimate the resulting casualties and fatalities. Examples of some of the health effect data used in the NARAC system are listed below:

  • Radiological Dose Conversion Factors: Dose conversion factors are combined with model-computed air and ground contamination levels to compute both acute radiation and longer-term chronic dose from inhalation, air submersion, and ground exposure. Dose factors are obtained from Oak Ridge National Laboratory and are based on methodologies documented in International Commission on Radiological Protections (ICRP) Publications.
  • Radiological Protective Action Guides (PAG) and Health Risk Levels: The U.S. Environmental Protection Agency (EPA) and the Department of Homeland Security (DHS) provide PAG dose levels to guide protective actions (sheltering, evacuation, and relocation) and to protect workers providing emergency services.
  • Chemical Exposure Guidelines and Limits: Chemical exposure air concentration levels of concern for (1) notable discomfort, (2) serious/long-lasting effects, and (3) life-threatening effects to sensitive populations are based on DOE Protective Action Criteria (PAC). The DOE PACs are drawn from a hierarchy of EPA Acute Exposure Guideline Levels (AEGL), American Industrial Hygiene Association (AIHA) Emergency Response Planning Guidelines (ERPG), and DOE Temporary Emergency Exposure Limits (TEEL).
  • Chemical Exposure Personal Protective Equipment Levels: The Centers for Disease Control and Prevention (CDC) National Institute for Occupational Safety and Health (NIOSH) Emergency Response Safety and Health Database (ERSH-DB) provides threshold concentration limits related to chemical-specific IDLH (Immediately Dangerous to Life and Health) and AEGL-1 values to define levels at which Personal Protective Equipment is warranted for chemical exposure.
  • Biological Agent Infection Levels: Infectious dose levels are drawn from multiple (mostly restricted) government sources.
  • Chemicals and Biological Agents Health Risks: Department of Defense (DoD) / Edgewood Chemical Biological Center (ECBC) reports provide data on health risks for chemicals and biological agents, from both inhalation and contact exposures.