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Biological and Chemical Contamination Procedures

Quick Summary​

Biological and chemical contamination creates extreme challenges in emergency situations, but with proper knowledge and techniques, these dangers can be overcome. This guide covers shelter construction, water procurement, food safety, and decontamination procedures for contaminated environments.

Why This Matters​

While rare, biological and chemical contamination scenarios can occur through:

  • Industrial accidents at chemical plants
  • Transportation incidents involving hazardous materials
  • Natural disasters affecting chemical storage facilities
  • Agricultural chemical spills
  • Biological contamination from disease outbreaks

Understanding these procedures could save your life and protect your family during such emergencies.

Shelter Construction in Contaminated Areas​

Location Selection​

Avoid These Areas:

  • Depressions in the ground (aerosol sprays concentrate here)
  • Areas with dense vegetation (provides protection for biological agents)
  • Downwind locations from contamination sources

Preferred Locations:

  • Open clearings away from vegetation
  • Elevated ground when possible
  • Areas with good air circulation

Construction Guidelines​

For Biological Contamination:

  1. Remove topsoil in the shelter area to decontaminate the ground
  2. Position entrance at 90-degree angle to prevailing winds
  3. Avoid using vegetation in shelter construction
  4. Keep shelter clean at all times
  5. Ensure good ventilation to prevent air stagnation

For Chemical Contamination:

  1. Build in clearings away from all vegetation
  2. Remove all topsoil in shelter area
  3. Keep entrance closed and angled away from prevailing winds
  4. Never burn contaminated wood - smoke will be toxic
  5. Use extreme caution entering shelter to avoid bringing contamination inside

Water Procurement Procedures​

Priority Order (Both Contamination Types)​

First Choice: Sealed Containers​

  • Safest option - assume contents are uncontaminated
  • Before opening: Wash container thoroughly with soap and water
  • Alternative: Boil container for at least 10 minutes
  • Then: Break seal and use water

Second Choice: Springs (Emergency Only)​

  • Use only when sealed water unavailable
  • Always boil for at least 10 minutes before drinking
  • Keep covered while boiling to prevent airborne contamination
  • For biological areas: This is your emergency backup

Last Resort: Standing Water (Extreme Emergency)​

  • Most dangerous option - vectors and germs thrive in stagnant water
  • Boil as long as possible to kill all organisms
  • Filter through cloth to remove dead organisms
  • Use water purification tablets in all cases

Chemical Environment Water Signs​

Never use water showing these contamination signs:

  • Foreign odors (garlic, mustard, geranium, bitter almonds)
  • Oily spots on surface or nearby
  • Dead fish or animals present
  • Unusual discoloration

Safer sources in chemical areas:

  • Underground water pipes
  • Fresh rainwater or snow (if no contamination evidence)
  • Slow-moving streams (check for signs first)

Food Safety Procedures​

Safe Food Sources​

Always Safe:

  • Your sealed emergency rations
  • Sealed cans or bottles (decontaminate exterior first)
  • Properly stored emergency food supplies

Decontamination Process:

  1. Wash all sealed containers with soap and water
  2. Or boil containers for 10 minutes
  3. Only then open and consume contents

Local Food (Use Only in Life-or-Death Situations)​

Critical Safety Note

No cooking method can guarantee removal of all biological or chemical agents. Use local food only when facing starvation.

If You Must Use Local Food:

Selection Guidelines:

  • Choose only healthy-looking plants and animals
  • Avoid known disease carriers (rats, vermin)
  • Use protective clothing and gloves when handling
  • Never eat raw food

Preparation Requirements:

  • Cook by boiling only - never fry, bake, or roast
  • Boil for minimum 10 minutes to kill pathogens
  • Boiling is the only safe cooking method - other methods may not reach required temperatures throughout

Detection Methods​

Chemical Agent Detection​

Physical Symptoms to Watch For:

  • Tears or difficulty breathing
  • Choking or coughing
  • Itching or skin irritation
  • Dizziness
  • Strange taste in food, water, or mouth

Visual Indicators:

  • Colored liquids or solids on surfaces
  • Mist or thin fog after explosions
  • Oily patches on leaves or buildings
  • Unusual colors on vegetation

Smell Indicators (Many agents are odorless):

  • Newly cut grass or hay smell (choking agents)
  • Almond smell (blood agents)
  • Unusual chemical odors

Sound Indicators:

  • Muffled explosions or shell detonations

Protection and Decontamination​

Personal Protection Priority​

  1. Use protective equipment (masks, clothing)
  2. Give immediate self-aid when contaminated
  3. Avoid contaminated areas completely when possible
  4. Decontaminate equipment and body as soon as possible

Decontamination Basics​

For Biological Contamination:

  • Wash thoroughly with soap and hot water
  • Change clothing if possible
  • Dispose of contaminated materials safely

For Chemical Contamination:

  • Remove contaminated clothing immediately
  • Wash skin with large amounts of water
  • Seek fresh air immediately
  • Avoid touching contaminated surfaces

Movement and Escape​

Leaving Contaminated Areas​

Best Routes:

  • Travel crosswind or upwind to reduce exposure time
  • Avoid downwind routes which keep you in the hazard area longer
  • Move to higher ground when possible
  • Seek medical attention immediately after leaving area

If You Must Remain​

  • Seal yourself in the safest available shelter
  • Monitor emergency broadcasts for updates
  • Conserve food and water supplies
  • Wait for official clearance before leaving

Modern Considerations​

Emergency Communication:

  • Battery-powered or hand-crank radio for updates
  • Cell phone (may not work in widespread emergencies)
  • Emergency whistle for signaling

Additional Supplies:

  • N95 or P100 masks for respiratory protection
  • Plastic sheeting and duct tape for sealing areas
  • Potassium iodide tablets (for nuclear incidents)
  • Extra batteries and flashlights

When to Seek Help​

Emergency Situations

Call 911 immediately if experiencing:

  • Severe breathing difficulties
  • Chemical burns on skin
  • Signs of poisoning (nausea, vomiting, confusion)
  • Severe skin or eye irritation

Professional Resources:

  • Local emergency management agencies
  • Poison control centers
  • Hospital emergency departments
  • HAZMAT teams

Safety Considerations​

Important Reminders
  • No food is worth your life - you can survive longer without food than with contaminated food
  • When in doubt, don't - avoid questionable food and water sources
  • Protect others - prevent spread of contamination
  • Follow official guidance - emergency authorities have better information and resources

, Emergency First Aid

Source

Adapted from Field Manual FM-3-05.70

Last updated: January 18, 2026