Carbon Monoxide Poisoning in Winter: Symptoms, First Aid, and When to Call an Ambulance

During winter, the increased use of stoves, boilers, water heaters, and similar heating devices -- combined with chimney blockages, poor ventilation, and equipment malfunctions -- raises the risk of carbon monoxide poisoning. Carbon monoxide (CO) is a colorless, odorless, and non-irritating gas, making it one of the most difficult poisons to detect. [1]Source: World Health Organization (WHO) - Carbon Monoxide — World Health Organization[2]Source: Centers for Disease Control and Prevention (CDC) - CO Poisoning — Centers for Disease Control and Prevention This guide walks you through CO symptoms, practical first aid steps you can apply at home, and clear criteria for when to call 112 or an ambulance.

What Is Carbon Monoxide (CO) and Why Is It Dangerous?

Carbon monoxide forms when fuels such as natural gas, coal, wood, and gasoline undergo incomplete combustion. When inhaled, CO passes from the lungs into the bloodstream and binds to hemoglobin far more strongly than oxygen, disrupting oxygen delivery to tissues throughout the body. [1]Source: World Health Organization (WHO) - Carbon Monoxide — World Health Organization This is why CO exposure can cause headache and nausea within minutes, progressing to loss of consciousness and life-threatening complications.

CO poisoning in winter commonly occurs in these scenarios:

Stove poisoning: Improper ignition, leaving the stove lit overnight, or using low-quality coal
Chimney blockage or reverse draft (caused by wind, bird nests, soot buildup, or lack of maintenance)
Boiler or water heater leaks or combustion problems
Generators or motor-powered devices running in enclosed spaces
Running a car engine in a closed garage or parking area

Why Is CO Poisoning More Common in Winter?

In winter, homes are kept sealed to retain heat. Windows stay closed for extended periods, ventilation grilles are blocked, and chimneys go uncleaned. These conditions cause indoor CO levels to rise. The danger is especially acute at night, when household members are asleep and CO accumulates to hazardous concentrations unnoticed.

Carbon Monoxide Poisoning Symptoms

CO poisoning symptoms are frequently mistaken for the flu, which delays recognition. [2]Source: Centers for Disease Control and Prevention (CDC) - CO Poisoning — Centers for Disease Control and Prevention The following complaints should raise suspicion of CO exposure, especially if multiple people in the same household develop symptoms simultaneously.

Early Symptoms

Headache (the most common symptom) [1]Source: World Health Organization (WHO) - Carbon Monoxide — World Health Organization
Dizziness and lightheadedness
Nausea and vomiting (headache and nausea often occur together)
Fatigue, weakness, and drowsiness
Shortness of breath (especially in those with heart or lung disease)
Palpitations and chest tightness

Moderate to Severe Symptoms

Difficulty concentrating, confusion (mental fog)
Loss of balance, difficulty walking
Visual disturbances
Loss of consciousness
Seizures, fainting
Cherry-red or unusually flushed skin (though this sign may be subtle or absent) [1]Source: World Health Organization (WHO) - Carbon Monoxide — World Health Organization and severe respiratory distress

Who Is at Higher Risk?

Infants and children
Elderly adults
Pregnant women
Those with heart disease, COPD, asthma, or other chronic conditions [1]Source: World Health Organization (WHO) - Carbon Monoxide — World Health Organization[2]Source: Centers for Disease Control and Prevention (CDC) - CO Poisoning — Centers for Disease Control and Prevention
People who are asleep when exposure occurs (nighttime stove/boiler scenarios)

First Aid for Carbon Monoxide Poisoning: What to Do at Home

The most critical action when CO poisoning is suspected is to stop the exposure immediately and provide fresh air. [1]Source: World Health Organization (WHO) - Carbon Monoxide — World Health Organization[2]Source: Centers for Disease Control and Prevention (CDC) - CO Poisoning — Centers for Disease Control and Prevention The following steps can be lifesaving until professional help arrives.

1) Ensure Your Own Safety First

CO is odorless, so a rescuer entering the space can quickly become affected as well. If possible:

Open doors and windows to ventilate the area.
If an unconscious person is inside, do not remain in the enclosed space alone and unprotected for a prolonged period.

2) Move the Person to Fresh Air

Take the affected person outdoors or to a well-ventilated area as quickly as possible.
Do not remain in the enclosed space; CO accumulation may still be ongoing.

3) Call 112 or Nova Ambulans and Describe the Situation Clearly

When calling 112 or Nova Ambulans (0216 339 00 39), provide the following information:

Suspected carbon monoxide poisoning (mention stove, boiler, or heater if applicable)
How many people are affected
Level of consciousness (awake, drowsy, or unconscious)
Full address and access details

4) Basic Checks for an Unconscious Person

Check whether they are breathing.
If there is no breathing and you are trained, begin CPR (basic life support). [3]Source: American Heart Association (AHA) — American Heart Association
Do not give food or drink to an unconscious person.
If the person is unconscious and vomiting, position them to protect the airway (if untrained, follow the phone guidance from 112 or Nova Ambulans).

5) Shutting Off the Source -- Exercise Caution

If it is safe to do so, the stove or boiler can be turned off. However, the priority is getting people out of the environment.
If shutting off a gas valve seems risky, do not waste time -- professional teams will handle it.

When Should You Call an Ambulance? (112 or Nova Ambulans)

Even seemingly mild CO exposure ("I just had a headache, it passed") can progress insidiously. In the following situations, do not delay calling an ambulance:

Always Call 112 or Nova Ambulans (0216 339 00 39) For:

Loss of consciousness, fainting, or unresponsiveness
Seizures
Severe shortness of breath, chest pain, or pronounced palpitations
Persistent vomiting, marked weakness, or excessive drowsiness
CO suspected in a pregnant woman, baby, child, elderly person, or someone with chronic disease
Similar symptoms appearing in multiple people in the same household simultaneously
Symptoms that do not fully resolve after moving to fresh air, or that recur shortly after

Why Is Medical Evaluation Important Even for "Mild" Cases?

Because CO disrupts tissue oxygenation, some individuals may appear to have minimal symptoms while still facing ongoing risk. Medical evaluation ensures appropriate treatment -- including oxygen therapy and hospital monitoring when needed -- and reduces the risk of delayed complications.

What Happens at the Hospital? (Brief Overview)

Medical teams will typically address CO poisoning with:

Oxygen therapy
Monitoring of vital signs (pulse, respiratory rate, blood pressure, oxygen saturation)
Necessary blood tests and physician assessment

The goal is to restore adequate oxygen delivery to tissues and minimize the risk of complications.

Winter Safety: Practical Tips to Prevent CO Poisoning

Carbon monoxide poisoning is largely preventable. The following precautions are critical during winter months:

For Stove Users

Have a plan to safely extinguish the stove before going to sleep; avoid leaving it burning overnight.
Burn coal properly; do not overload the stove.
Ventilate the room regularly.

Chimney Blockage and Maintenance

Have chimneys cleaned regularly to reduce soot buildup and blockage risk.
Be aware that strong winds can cause reverse drafts; if you develop a headache or dizziness, think of CO.

Boiler and Water Heater Safety

Schedule periodic maintenance for your boiler combustion system.
Do not seal ventilation grilles; ensure the room where the device is located has adequate airflow.
If you feel sudden weakness or dizziness in the bathroom while the water heater is running, leave the area immediately.

CO Alarm Devices

Installing carbon monoxide alarms in appropriate locations provides early warning [2]Source: Centers for Disease Control and Prevention (CDC) - CO Poisoning — Centers for Disease Control and Prevention (especially near stoves, boilers, and bedrooms).
Test alarms periodically and replace batteries as recommended.

Private Ambulance Support in Istanbul: Nova Ambulans

In suspected carbon monoxide poisoning, rapid and accurate triage can be lifesaving. Nova Ambulans provides 24/7 emergency ambulance service in Istanbul with professional crews and appropriate equipment for both emergency situations and patient transport needs. In CO exposure, the correct approach is to move the person safely to fresh air, call 112 or Nova Ambulans (0216 339 00 39), and not delay medical evaluation. The key difference: 112 transports to the nearest public hospital, while Nova Ambulans can take you to the private hospital of your choice.

Conclusion

During winter, carbon monoxide poisoning can strike suddenly due to stove, boiler, and chimney-related risks. It often starts with flu-like symptoms but can escalate rapidly. Take early signs such as headache, nausea, and dizziness seriously -- especially if multiple household members are affected simultaneously. In first aid, the priority is fresh air and rapid medical assistance. For loss of consciousness, shortness of breath, chest pain, or exposure involving pregnant women, children, or the elderly, call 112 or Nova Ambulans (0216 339 00 39) without hesitation.

Frequently Asked Questions

Where should carbon monoxide detectors be placed in a home?

Install at least one CO detector on every floor, near sleeping areas, and at ceiling height or on a wall 15-30 cm below the ceiling (per EN 50292 standard). Avoid placing detectors directly next to fuel-burning appliances, windows, or in bathrooms where steam may cause false alarms.

What are the earliest symptoms of carbon monoxide poisoning?

The earliest symptoms include headache, dizziness, nausea, and fatigue. Because these mimic flu symptoms, a key warning sign is when multiple people in the same enclosed space develop similar complaints simultaneously.

What should I do immediately if I suspect CO poisoning?

Open all windows and doors, turn off all fuel-burning appliances, evacuate everyone from the building, and call 112 or Nova Ambulans immediately. Do not re-enter the building until emergency services confirm it is safe.

How is carbon monoxide poisoning treated?

Treatment involves high-flow oxygen therapy to displace CO from hemoglobin. In severe cases, hyperbaric oxygen therapy in a specialized chamber may be required. Early medical intervention significantly improves outcomes.