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Community Connection

Be Safe. Be informed.

Do you know what to do in case of a chemical emergency?

This page is designed to give you and your family the information and tools you need to be prepared in case there is a chemical emergency.


What is Shelter-In-Place?

Shelter-in-place is a proven and effective method of protecting both you and your family from the hazardous effects of chemical accidents, such as liquid chemical spills, vapor releases and fires involving hazardous materials. Such accidents, while rare, could happen at any time and virtually anywhere. Possible sources of a chemical emergency include manufacturing facilities, chemical plants, warehouses, retail establishments, farms, agricultural product centers, gas stations, and transportation (such as trucks and rail cars).

How do I Shelter-in-Place?

  1. When the Community Notification System is activated, immediately take your family and pets indoors.
  2. Tightly close and latch all doors and windows
  3. Turn off all fans, heating and air conditioning systems
  4. Close fireplace dampers and any other vents to the outside
  5. Go to an above-ground room (not the basement) with as few windows as possible and close the door. Gather your emergency supply kit (see below).
  6. Go to an above-ground room (not the basement) with the fewest windows and close the door.
  7. Stuff damp towels in the open space between the floor and the door.
  8. If necessary, seal doors, windows and any vents with duct tape and plastic sheeting.
  9. If you smell chemicals, breathe through wet washcloths or towels.
  10. Stay in the room and listen to the radio or watch TV for further instructions.
  11. If told to evacuate, follow instructions given by emergency personnel.

Frequently Asked Questions

When should I shelter-in-place?
Why not evacuate?
What if I’m in a vehicle?
What about children at school?
Why an above ground room?
How will I know it is safe to go outside?
Should I call 911 for information?
What media sources will have emergency information?
What about emergency supplies?
What do the siren sounds mean?
What is the siren alarm / emergency system testing schedule?

When should I shelter-in-place
You should follow the shelter-in-place procedures whenever you receive notification of a chemical emergency. This may be broadcast over the radio or cable television, directly by emergency personnel, or by the Community Notification System (such as sirens or telephone alerts). You should also shelter-in-place when you see or smell any unusual chemicals in the air.
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Why not evacuate?
While evacuations may be needed in rare situations, there would normally not be enough time to safely evacuate all affected individuals. Evacuation also endangers emergency personnel and individuals being evacuated by potentially exposing them to the chemicals in question.
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What if I’m in a vehicle?
If you are inside a vehicle during a chemical emergency, stop the vehicle at a safe location as soon as possible. Do not attempt to drive home or to another location. Shut off the vehicle’s engine, and follow the same basic shelter-in-place procedures. Roll up the windows, close vents, and turn on the radio for further instructions.
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What about children at school?
If your children are at school or other care provider, do not attempt to get them. Doing so could put you and them in danger. They are safest at school until the emergency is over.
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Why an above-ground room?
Unlike a tornado emergency, basements are not recommended shelter locations for chemical accidents. Most chemicals are heavier than air and will seek low lying areas, like basements. So, an above-ground room is the safest spot during a chemical emergency. If you do not have an above-ground room, a ground-level room will work fine. If possible, select a room on the side of the house opposite from the source of the chemical.
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How will I know it is safe to go outside?
This will depend on the nature and location of the emergency, but could occur in one of several ways: radio, television, directly by emergency personnel or via the Community Notification System (such as sirens or telephone alerts).
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Should I call 9-1-1 for information?
Authorities request that you not call 911 unless you have an emergency or need immediate assistance. Non-emergency calls to 911 will tie up phone lines and dispatch personnel, preventing them from addressing true emergencies.
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What media sources will have emergency information?
Tune into your local media outlets for additional emergency information.
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What should I have in my emergency supply kit?
It is recommended that you have supplies assembled for all types of emergencies, including chemical accidents. Suggested items for chemical emergencies include: bottled water, towels & washcloths, plastic sheeting, duct tape, scissors (for cutting plastic), radio, flashlight, extra batteries, and a first aid kit.
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What do the siren sounds mean?

On-Site Sirens:

Tornado Warning

Muster Alert

Building Evacuation

Site Evacuation
The Tornado Warning, Muster Alert, Building Evacuation, and Site Evacuation sirens mean that Hemlock Semiconductor employees and contractors need to take action by either sheltering-in place or evacuating a building/area. Even though you may hear them, these sirens are meant for those groups only.
Warning Sirens in the CommunityThe sirens are activated by Saginaw County
9-1-1 and are used to alert the community in the event of severe weather or a chemical accident.
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What is the siren alarm / emergency system testing schedule?

Alarm / SystemFrequencySchedule
Site Building Evacuation,
Site Evacuation Siren, Muster

Alarms and
Tornado Alert
Bi-AnnuallyFirst Wednesday of January and July at Noon
Saginaw County
9-1-1 Community Warning Sirens
MonthlyFirst Wednesday of the month*:
• May-September at 7 p.m.
• October-April at Noon
* Time affects when phone, text and/or email notifications are received

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No Alert
Info. line:642-2800
Alert Key

Register for the Saginaw County 911 Emergency Notification System.

Download Chemical
Fact Sheets

Chlorosilanes PDF 
Monosilanes PDF 
Hydrogen Chloride PDF 
Silicon Tetrachloride PDF
Trichlorosilanes  PDF


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