Winter Home Safety Checklist: Carbon Monoxide, Space Heaters & Humidifiers

Carbon monoxide is one of the most dangerous winter risks because you can’t see, smell, or taste it.
It’s produced by fuel-burning appliances, including:

• furnaces
• fireplaces
• wood stoves
• water heaters
• gas stoves
• generators
• cars left running in garages

Because CO is completely undetectable without an alarm, exposure often goes unnoticed until symptoms appear.

Common CO Exposure Symptoms

These often mimic a viral illness:

• headache
• dizziness
• nausea
• fatigue
• shortness of breath
• confusion
   

That overlap is why so many CO cases go undetected in winter.

✔️ Your Essential CO Safety Checklist

A few simple steps dramatically reduce risk:

1. Install CO detectors on every level of your home

Place them near sleeping areas for early detection.

2. Test alarms monthly

It takes less than 30 seconds.

3. Replace batteries yearly

Many people wait until alarms chirp — don’t.

4. Keep outdoor vents clear of snow and debris

Snow drifts can block furnace or water heater exhaust vents, trapping CO inside the home.

5. Open fireplace flues

Always open the damper fully before lighting a fire.

6. Never run a car in an enclosed garage

Even with the door partially open, CO builds up quickly.

Just one blocked vent or malfunctioning heater is enough to cause dangerous CO levels.

— not from the heater itself.

Follow these safety basics:

• Keep 3 feet of space around heaters

No blankets, curtains, bedding, or furniture nearby.

• Plug heaters directly into the wall

Avoid power strips or extension cords, which overheat easily.

• Choose models with automatic shut-off

Especially those that turn off if tipped over.

• Turn heaters off when sleeping or leaving a room

Unattended heaters are the leading cause of winter house fires.

A few small adjustments make these devices significantly safer.

Winter dryness can trigger nosebleeds, coughing, dry skin, and congestion. Humidifiers help — but only when clean.

Dirty tanks can release:

• mold
• bacteria
• mineral dust
• irritants that worsen asthma or allergies
   

Here’s how to use humidifiers safely:

• Use distilled or filtered water when possible

This reduces mineral buildup.

• Empty and dry tanks daily

Stagnant water is the fastest way for bacteria to multiply.

• Deep-clean weekly

Follow the manufacturer’s instructions or use a white-vinegar rinse.

• Keep humidity between 30–50%

Too much humidity encourages mold; too little dries out airways.

Humidifiers are incredibly helpful — but they require regular maintenance.

In cold weather, it’s natural to keep windows closed for long stretches. But indoor air becomes stagnant, trapping:

• CO (if present)
• dust
• chemicals
• allergens
• dry, recycled air
• wood-burning particles
   

A quick ventilation routine prevents buildup without losing much heat.

Ventilation Tip:

Crack a window for 5–10 minutes each day.
It refreshes air circulation and dramatically improves indoor air quality.

If you experience:

• dizziness
• nausea
• headache
• confusion
• chest tightness
• overwhelming fatigue
   

especially after being indoors, treat it as a potential CO or air-quality exposure.

This is a medical situation — and early evaluation is critical.

CallOnDoc can help assess symptoms, provide guidance, and help determine if further emergency care is needed.