What to do in case of a chemical release

Information note on chemical release No 2
May 2017
What to do in case of a chemical release
If the release is inside a building or a closed space, you should do whatever it takes to find
clean air quickly: exit the building without passing through the contaminated area or break a
window to access clean air.
If you are out of doors in an area where a chemical has been released, you should:
1. Avoid any obvious plume or vapour cloud. Cover your mouth and nose and, if
possible, any exposed skin (e.g. roll down sleeves, button up coat/jacket).
2. Move away from the source, try and move upwind from the agent (so the wind is
blowing the chemical away from you) or crosswind.
3. Go into a building in order to shelter-in-place. Select a room with the following
on a high floor and with as few windows as possible
if possible the room should have access to a bathroom and should have
a telephone,
4. If you may have been exposed to a chemical then you must decontaminate yourself
before entering the room
5. Try to seal the room to create a temporary barrier between clean air inside and
contaminated air outside:
• Close all windows, doors, air vents, and fireplace dampers and seal, if
possible, with plastic sheeting and duct tape or improvise a seal with
whatever is to hand e.g. wet towels
• Turn off fans, air conditioning, and forced air heating systems
• NB in a completely sealed room the air will eventually become depleted of
oxygen, therefore after a few hours you will need to open a source of
ventilation or leave the room – use your judgement about this.
• Do not burn a carbon-based fuel, i.e. paper, coal, wood, gas or oil for heating
or cooking since, if the fresh air supply is restricted, burning these fuels will
produce carbon monoxide, which is poisonous.
6. Watch TV, listen to the radio, or check the Internet often for official news and
instructions as they become available.
7. Evaluate your situation and, when you judge it to be safe, evacuate the area and
relocate to a safer place.
If you are contaminated or exposed to chemical agents avoid contact with others as you
may cause secondary contamination. Take the following steps:
1. Remove your clothing as quickly as possible. Avoid pulling clothing over your head –
cut the clothes off if necessary.
2. Wash your whole body, including your hair, with soap (preferably liquid soap) and
tepid water, or with water alone. Rinse skin with copious amounts of water
3. Rinse your eyes with water.
4. Put on clean clothes.
5. Place contaminated clothes in a strong plastic bag. Avoid touching contaminated
clothes with your bare hands – use an implement or wear thick rubber gloves. Put
any contaminated personal effects or other objects into the same bag. Close and seal
this bag securely and, if possible, put the bag into another bag and close that tightly.
The contents of the bag are contaminated so put a warning on the bag and put the
bag in a secure place outside until it can be disposed of.
6. Seek medical attention if you have been exposed, even if you have no immediate
How this advice was developed
This advice was developed by a small working group convened by WHO. The group included national
experts from Germany, Norway and the UK who work on CBRN preparedness and response, and
occupational health and safety professionals with expertise in protection from chemical weapons
exposure. Reference was also made to Patient Decontamination in a Mass Chemical Exposure
Incident: National Planning Guidance for Communities. Washington (DC): US Department of Health
and Human Services and US Department of Homeland Security; 2014.