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Life-Saving Safety Guide

Carbon Monoxide Safety:
The Silent Killer in Your Home

Carbon monoxide kills over 400 Americans per year and sends 50,000 to the ER. You cannot see it, smell it, or taste it. Symptoms mimic the flu. By the time you realize something is wrong, you may not be able to call for help.

Kidde Carbon Monoxide Detector

If you do nothing else on this page

Buy a CO detector. Install it tonight. It costs $20. Not having one is gambling with your family's life.

This Kidde plug-in CO alarm has battery backup, a digital display showing CO levels, and peak level memory. Install outside every bedroom.

Get the CO Detector — $20 Could Save Your Life →

CO Poisoning Symptoms by Concentration

CO Level (ppm) Exposure Time Symptoms
1-4 ppm Normal home levels No symptoms. Safe range.
10-30 ppm Hours Mild headache, slight fatigue
35-100 ppm 1-2 hours Severe headache, dizziness, nausea, confusion
100-200 ppm 1-2 hours Severe symptoms, impaired judgment, possible fainting
200-400 ppm 1-3 hours Life-threatening. Loss of consciousness, seizures
400+ ppm Minutes FATAL. Unconsciousness, brain damage, death

The "Flu" Test — How to Tell if It Is CO Poisoning

CO poisoning is called "the great imitator" because symptoms mimic the flu. Here is how to tell the difference:

Likely CO Poisoning

  • ✓ Everyone in the house is sick at the same time
  • ✓ Symptoms improve when you leave the house
  • ✓ Symptoms return when you go back inside
  • ✓ No fever (CO poisoning rarely causes fever)
  • ✓ Pets are also acting lethargic or sick

Likely the Flu

  • ✓ Only one person is sick (usually)
  • ✓ Symptoms persist regardless of location
  • ✓ Fever is present
  • ✓ Symptoms develop over days, not hours
  • ✓ Body aches and sore throat

What to Do When Your CO Alarm Sounds

  1. 1

    Evacuate Immediately

    Get everyone out of the house. Do not stop to gather belongings. Leave doors open to ventilate. Account for all family members and pets.

  2. 2

    Call 911 from Outside

    Call from your cell phone or a neighbor's phone. Do NOT go back inside to use the phone. Tell the dispatcher you have a CO alarm.

  3. 3

    Do Not Re-Enter

    Wait for fire department to confirm the air is safe. They have professional CO meters. Even if you feel fine, CO continues building in your blood for hours.

  4. 4

    Seek Medical Attention

    If anyone has symptoms (headache, dizziness, nausea), go to the ER. Request a blood carboxyhemoglobin (COHb) test. CO poisoning can cause delayed neurological damage even days after exposure.

  5. 5

    Find and Fix the Source

    Hire a professional to inspect all fuel-burning appliances: furnace, water heater, stove, fireplace, generator. Never use a gas stove for heating or run generators indoors.

Common Sources of CO in Homes

High-Risk Sources

  • Gas or oil furnaces (cracked heat exchanger)
  • Portable generators (NEVER run indoors or in garage)
  • Gas stoves and ovens (especially used for heating)
  • Cars idling in attached garages
  • Blocked chimney or flue

Other Sources

  • Gas water heaters (improper venting)
  • Wood-burning fireplaces (closed damper)
  • Gas-powered lawn equipment in enclosed spaces
  • Charcoal grills used indoors
  • Boat cabins with engines running
Smoke and CO Combo Detector

Combined Smoke + CO Alarm — 10-Year Sealed Battery

One device detects both threats. Sealed 10-year battery means no midnight chirping from low batteries. Install on every level and outside every bedroom.

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Where to Install CO Detectors

✅ Do

  • ✓ One on every level of your home, including basement
  • ✓ Outside every sleeping area (so it wakes you up)
  • ✓ At least 5 feet above the floor on a wall
  • ✓ In or near rooms with fuel-burning appliances
  • ✓ Where you can hear it from bedrooms

❌ Don't

  • ✗ Right next to a gas stove or furnace (false alarms)
  • ✗ In dead air spaces (corner of room, behind furniture)
  • ✗ Near windows or doors (fresh air dilutes readings)
  • ✗ In bathrooms (humidity can damage sensors)
  • ✗ Directly above fuel-burning appliances

Frequently Asked Questions

How long does CO stay in your body?

The half-life of CO in your blood is about 4-6 hours breathing normal air. With 100% oxygen therapy at the hospital, it drops to 60-90 minutes. In a hyperbaric chamber, it can be as fast as 20-30 minutes. This is why hospital treatment is critical after significant exposure.

Can a low CO level still be dangerous?

Yes. Chronic low-level CO exposure (10-30 ppm) over weeks and months causes persistent headaches, fatigue, brain fog, and depression. It is often misdiagnosed as chronic fatigue syndrome, fibromyalgia, or depression. If your doctor cannot figure out what is wrong, ask about CO testing.

Do CO detectors expire?

Yes. Most CO detectors have a 5-10 year lifespan. Check the manufacture date (not the purchase date). After expiration, the sensor degrades and may not detect CO. Replace immediately when expired. Write the expiration date on the unit with a marker.

Are gas stoves a CO risk?

Yes, especially if the flame is not properly adjusted (yellow tips instead of blue). A properly adjusted gas stove produces minimal CO, but any gas combustion produces some. Always run the exhaust fan when cooking. Never use a gas oven for home heating.

400+ Americans Die From CO Poisoning Every Year

Almost all of them did not have a working CO detector. A $20 detector is the cheapest life insurance you will ever buy. Install one on every level tonight.

Get the CO Detector — Protect Your Family Tonight →
Medical Disclaimer: This guide is for informational purposes only and does not constitute medical advice. CO poisoning is a medical emergency. If you suspect CO exposure, evacuate immediately and call 911. Data sourced from publicly available CDC, EPA, and CPSC publications.

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