|What is Shelter-in-Place?
In a situation where a serious hazardous chemical spill
has quickly caused a toxic atmosphere, it may be more
dangerous to go through those toxic vapors or to attempt
to outrun them than to stay in an existing structure.
Shelter-in-Place means to get to the inside of a building
and remain there during a chemical emergency rather than
attempting to evacuate the area. Shelter-in-Place is a
viable option for protection against exposure to potentially
dangerous airborne chemicals during an emergency.
SHELTER-IN-PLACE DOES NOT APPLY TO FLAMMABLE GASES SUCH
AS PROPANE AND NATURAL GASES.
During a hazardous materials incident, the idea
is to keep everyone's exposure to any chemical
as low as possible. It is best to get out of the
area and have no exposure, but in a sudden chemical
release there may not be time to safely
evacuate. In such cases, attempts
to evacuate could place you at greater risk of
exposure than if you had stayed in your home or
workplace. Shelter-in-place is used when there
has been a serious hazardous chemical spill that
has quickly caused a toxic atmosphere and there
is not enough time to safely leave the area. When
you shelter-in-place, you take protective action
in a structure to reduce exposure to toxic chemical
levels. So, unless otherwise instructed to evacuate,
sheltering-in-place could be the best way to safely
wait out a hazardous chemical release.
How safe is it to Shelter-in-Place?
In a 2001 report by The National Institute for
Chemical Studies, several studies were cited that
demonstrate the value of sheltering-in-place during
a chemical emergency. In older homes, the average
house was found to change its air at a rate of
less than 1/3 change per hour. It was also found
that if one room in the house was sealed up with
duct tape and plastic, the amount of chemical
that was in the room after one hour was between
1/7 to 1/17 of what was outside. Another study
found that sealing up a house also filtered out
some of the chemicals. Not only did a sealed up
house limit the amount of air coming into a house,
the walls actually did some filtering of the air
that seeped in. Sheltering-in-place cannot completely
eliminate all exposure to the chemical, but it
can keep the exposure below dangerous levels.
The report concluded: "For the vast majority
of events that have led to the public to shelter-in-place,
there have been no reported injuries. In fact,
for a very few cases, clouds of toxic materials
of sufficient concentration to cause harm have
entered communities and, because sheltering-in-place
has been accepted by the community and was successfully
implemented, no one was injured. The body of evidence
suggests that if there is insufficient time to
complete an evacuation or the chemical leak will
be of limited duration, or conditions would make
an evacuation more risky than staying in place,
sheltering-in-place is a good way to protect the
public during chemical emergencies."
When should I Shelter-in-Place?
A hazardous materials accident can occur anywhere.
There may even be a time when you are close to
where a chemical accident has taken place. If
you feel or hear a strange sound like an explosion;
if you see a strange cloud; if you smell a strange
odor; if you feel nauseous or have burning or
tearing eyes; trust your senses, don't wait for
a warning confirmation and act immediately. If
it is obvious that you can safely evacuate the
area, do so, but remember shelter-in-place as
the next option.
Where do I Shelter-in-Place?
If you are told to shelter-in-place or if you
believe you need to, you should go inside any
building close by immediately. If you are not
by your own house, a church, school, or store
are good options. If you are not near any buildings,
your car is a better choice than staying outside.
Your home is the best choice to shelter-in-place
because you will know where tapes, towels, plastics
and other items are located to help you create
your shelter space.
How do I Shelter-in-Place?
- Close all doors to the outside and close and lock
all windows (windows sometimes seal better when locked.)
- Ventilation systems should be turned off so no
outside air is drawn into the structure.
- Turn off all heating systems and all air-conditioners
and switch inlets to the "closed" position.
- Seal any gaps around window type air-conditioners
with tape and plastic sheeting, wax paper, or aluminum
- Turn off all the exhaust fans in kitchens, bathrooms
and attics, and cover the openings with plastic wrap
or plastic sheeting.
- Close all fireplace dampers and seal with plastic
- Close as many internal doors as possible in the
structure you are in.
- Pick a room on the highest level of the structure,
as most of the chemicals that are of concern are heavier
than air and will settle in the basement.
- Select a room in the building that is comfortable
and easy to seal off. The room should, if possible,
provide access to water, toilet facilities, and have
adequate room for people and pets to sit.
- If the vapor begins to bother you place a wet cloth
over your nose and mouth. For a higher degree of protection,
go into the bathroom, close the door and turn on the
shower in a strong spray to "wash" the air.
Seal any opening to the outside of the bathroom as
best you can.
- Make sure you have a battery-powered radio and
a flashlight in case the power goes out.
- Once in the room, seal windows, air vents, and
exhaust fans with plastic sheeting and duct tape.
- In some homes, light switches and electrical outlets
on outside walls are sources of air infiltration and
should also be sealed with duct tape and plastic.
- Lastly, seal around the door with duct tape. If
the space under the door is too big to seal with tape,
try stuffing a damp towel under the door.
- Continue to listen to the radio or TV for emergency
information and updates on the incident.
- Don't call 911 unless you have an emergency like
a fire or a serious injury.
- Keep your phone available in case someone needs
to contact you.
What if I can't make it to a building?
If you can get to your car, go there. Turn off the ventilation
system, close your windows and vents, and tune your
radio to a local station. If you are driving, try to
avoid driving through a vapor cloud and try to drive
crosswind. If you are in a chemical cloud, be aware
that your car may stall. If your car stalls or was not
running when enveloped by the cloud, DO NOT try to start
it unless told to do so by a public announcement on
If you are outside and not close to a building, such
as being on a golf course or in a rural area, try to
move crosswind. The vapors may drift downwind for miles
and unless there is no wind at all you will not be able
to outrun them. Going perpendicular to the wind, away
from the center of the cloud will get you to a less
harmful atmosphere quicker.
How will I know it is safe to come out?
As soon as it is deemed safe, authorities will tell
you it is safe to leave your building.
Disaster supplies to have on hand.
- Flashlight and extra batteries
- Portable battery-operated radio
- Duct tape and plastic sheeting & wrap
- Games and toys to occupy children
- First aid kit and essential medicines
- Emergency food and water
SPECIAL NOTE: SHELTER-IN-PLACE DOES NOT APPLY TO FLAMMABLE
GASES SUCH AS PROPANE AND NATURAL GASES.