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  5. Protective Action Decision Factors to Consider

Protective Action Decision Factors to Consider

The choice of protective actions for a given situation depends on a number of factors. For some cases, evacuation may be the best option; in others, sheltering in-place may be the best course. Sometimes, these two actions may be used in combination. In any emergency, officials need to quickly give the public instructions. The public will need continuing information and instructions while being evacuated or sheltered in-place.

Proper evaluation of the factors listed below will determine the effectiveness of evacuation or in-place protection (shelter in-place). The importance of these factors can vary with emergency conditions. In specific emergencies, other factors may need to be identified and considered as well. This list indicates what kind of information may be needed to make the initial decision.

The Dangerous Goods

  • Degree of health hazard
  • Chemical and physical properties
  • Amount involved
  • Containment/control of release
  • Rate of vapor movement

The Population Threatened

  • Location
  • Number of people
  • Time available to evacuate or shelter in-place
  • Ability to control evacuation or shelter in-place
  • Building types and availability
  • Special institutions or populations, e.g., nursing homes, hospitals, prisons

Weather Conditions

  • Effect on vapor and cloud movement
  • Potential for change
  • Effect on evacuation or shelter in-place
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