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On-site Activities

Major Goals of the Initial Response

  1. Notify local authorities

  2. Establish local on-site Incident Command System (FEMA)
  3. Establish Control Zones:
    • Estimation of protective distance/threat zone
    • Hotzone/perimeter security
      • Rescuers should be trained and appropriately attired before entering the Hotzone. If the proper equipment is not available, or if rescuers have not been trained in its use, call for assistance from a local or regional HAZMAT team or other properly equipped response organization.
      • Rescuer Protection - When a chemical is unidentified, worst-case possibilities concerning toxicity must be assumed. The potential for severe local effects (e.g., irritation and burning) and severe systemic effects (e.g., organ damage) should be assumed when specific rescuer-protection equipment is selected.
        • Respiratory Protection: Pressure-demand, self-contained breathing apparatus (SCBA) should be used in all response situations.
        • Skin Protection: Chemical-protective clothing should be worn when local and systemic effects are unknown.
        • See Personal Protective Equipment (PPE) Guidelines

    • Decontamination Zone
      • Position the decontamination corridor upwind and uphill of the hot zone.
      • The warm zone should include two decontamination corridors. One decontamination corridor is used to enter the warm zone and the other for exiting the warm zone into the cold zone. The decontamination zone for exiting should be upwind and uphill from the zone used to enter.
      • Decontamination area workers should wear appropriate PPE.
      • Victims who are able and cooperative may assist with their own decontamination. Remove and double-bag contaminated clothing and personal belongings.
      • Flush exposed or irritated skin and hair with plain water for 3 to 5 minutes. For oily or otherwise adherent chemicals, use mild soap on the skin and hair.
      • Flush exposed or irritated eyes with plain water or saline for at least 5 minutes. Remove contact lenses if present and easily removable without additional trauma to the eye. If a corrosive material is suspected or if pain or injury is evident, continue irrigation while transferring the victim to the Support Zone.
      • In cases of ingestion, do not induce emesis. Victims who are conscious and able to swallow should be given 4 to 8 ounces of water. Obtain medical care immediately.

    • Support Zone
      • As soon as basic decontamination is complete, move the victim to the Support Zone.
      • Be certain that victims have been decontaminated properly (see Decontamination Zone above). Victims who have undergone decontamination or who have been exposed only to gas or vapor and who have no evidence of skin or eye irritation generally pose no serious risks of secondary contamination. In such cases, Support Zone personnel require no specialized protective gear.

  4. Ensure safety of responders
    • Establish and observe boundaries of Hotzone, Decontamination Zone, and Support Zone.
    • Wear appropriate personal protective equipment (PPE)
    • Avoid secondary contamination as victims are transported away from Hotzone.

  5. Identify specifics of the chemical hazard
  6. Consider the Population Threatened
    • Identify approximate number and location of casualties and injuries.
    • Identify if there is time for and the ability to control an evacuation; see specific populations for information on special institutions or populations, e.g., nursing homes, hospitals, prisons, schools.
    • Ensure the needs of specific populations are being addressed.
    • Identify nature of the site affecting response procedures:
      • Have critical infrastructures (e.g., electrical power, water supplies, sanitation, telecommunications, transportation, etc.), medical and healthcare facilities been affected? If so, in what way?
      • Are escape routes open and accessible?
      • What geographical area(s) has been or may be adversely impacted?
      • Estimation of protective distance/threat zone
    • Consider how current and forecasted weather conditions will affect the situation?
      • National Weather Service
      • Evaluation for effect on vapor cloud movement
      • Potential for changing weather
      • Effect on sheltering or evaluation procedures

  7. Begin triage of patients using protocols appropriate for the chemical emergency.
    • Alert local medical infrastructure to prepare for mass casualty transports.

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Protective Actions

  • Protect the public from further injury by implementing Protective Actions (Emergency Response Guidebook 2016) appropriate for the incident. Continue to gather information and monitor the event so that protective actions can be modified based upon each changing situation as needed, or until the threat is removed.

  • Actions taken to reduce or eliminate the emergency responders' and the public's exposure to hazard following an the incident include:
  • Evacuation: make sure there is enough time to inform people and move all people from a threatened area
    • Start with those closest to the scene then expand
    • Give people a specific route to follow to a place that is far enough away to keep them safe if the wind shifts

  • Shelter-in place: should be used when evacuation would cause greater risk than staying in place or evacuation cannot be performed. Shelter-in place should not be used if the vapors are flammable, if buildings cannot close tightly, or if the gas will take a long time to clear the area.
    • People should seek shelter inside and remain until the danger passes
    • Close all doors and windows inside the building, and turn off any ventilation or air movement systems (heat, air conditioning, etc.)
    • Vehicles can be used as long as closed tightly but are not as good as buildings
    • Keep communication with those inside the buildings
    • Advise those inside to stay away from windows to avoid glass fragments upon explosion

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  1. Medical Management Guidelines for Unidentified Chemical (HHS/CDC/ATSDR)
  2. Protective Action Decision Factors to Consider (Emergency Response Guidebook 2016, Department of Transportation, Pipeline and Hazardous Materials Safety Administration (PHMSA))
  3. Emergency Room Procedures in Chemical Hazard Emergencies A Job Aid (HHS/CDC)
  4. Public Health Emergency Response Guide for State, Local, and Tribal Public Health Directors. Version 2.0. (PDF - 200 KB) (HHS/CDC)
  5. Emergency Response Guidebook 2016. (entire document, PDF - 4.7 MB) (or online version at Transport Canada) (Department of Transportation, Pipeline and Hazardous Materials Safety Administration (PHMSA))

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