Seasonal CO Safety Check

Carbon monoxide risks change with the seasons, and so should your safety habits. In 2015, the year CDC broke out by month, 36 per cent of the 393 unintentional CO deaths in the United States fell in December, January or February, when heating systems run continuously and homes are sealed against the cold. But CO is not only a winter problem: summer brings generator use during hurricane-season power outages, boating risks, and camping with gas equipment; fall brings first-furnace-use hazards; and spring brings blocked vents from winter debris and animal nests.

Most seasonal CO incidents follow a predictable pattern: a maintenance task was skipped, a vent was blocked, or equipment was used in the wrong place. These are preventable failures, but they require awareness of what to check and when.

This 2-minute seasonal check evaluates your home across four dimensions: heating system readiness, ventilation and vent clearance, generator and outdoor equipment safety, and detector and emergency readiness. You will receive an overall seasonal preparedness score and a specific action list for the current time of year.

Annual chimney cleaning is on every safety checklist ever written, this one included, and it is almost never anybody's legal duty. Across the 93 municipal codes and 51 state instruments we have read, Shreveport, Louisiana is the only place that writes the alarm and the flue into the same sentence. Section 23.8(C) of its Unified Development Code lists what a short-term rental must have in place at all times while occupied, and in one clause it requires smoke detectors, carbon monoxide detectors and fire extinguishers to be installed and operable and all wood-burning fireplaces and stoves to be cleaned annually. That pairing is the right instinct and the rarity of it is the point: a blocked flue is the mechanism behind a large share of residential poisonings, so the alarm is the second line of defence and the sweep is the first. Shreveport also attaches no fuel-burning trigger, so a short-term rental there with nothing burning in it still owes the detector.

Note: This check provides general seasonal safety guidance based on CPSC, NFPA, CDC, and FEMA recommendations. It is not a substitute for a professional HVAC inspection.

In 2 Minutes

• 36 per cent of CO deaths fell in December, January and February in the year CDC counted, 2015, out of 393 unintentional CO deaths that year. Risks exist in every season.
• January and December are the months CDC reports most often, across poison-centre calls, emergency department visits, hospitalizations and deaths alike, in its 2005 to 2018 study.
• The first furnace use of the season is a high-risk moment, cracked heat exchangers may have developed over summer.
• Snow and ice blocking exterior vents is a leading winter CO cause that homeowners often overlook.
• Hurricane-season generator misuse causes a spike in CO deaths every year.
• This check scores your readiness for the current season across heating, ventilation, equipment safety, and detector preparedness.

What This Check Covers

• Whether your heating system has been professionally inspected for the current season.
• Whether exterior vents, chimneys, and flue pipes are clear of seasonal blockages.
• Whether you have a generator or outdoor fuel-burning equipment and how you plan to use it.
• Whether your CO detectors are functional, within their rated lifespan, and have working batteries.
• Whether you have a CO emergency plan that your household knows.
• Season-specific risks based on the current time of year.

Start the Check

How to Interpret Your Result

Your answers are scored across four seasonal safety dimensions: heating readiness, ventilation clearance, equipment safety, and detector/emergency preparedness.

• Seasonally Prepared (80-100%): Your home scores high across all four seasonal CO safety dimensions for the current time of year.
• Mostly Ready (60-75%): Solid seasonal foundation, but one or two areas need attention for the current time of year.
• Seasonal Gaps Found (40-55%): Multiple CO safety gaps relevant to the current season. The combination creates meaningful seasonal risk.
• Immediate Seasonal Action Needed (0-35%): Significant CO safety gaps across most or all seasonal dimensions. Your home is not adequately prepared for the CO risks of the current season.

Sources & References

1. CPSC, CO Information Center . CPSC's CO hub: "More than 200 people in the United States die every year from accidental non-fire related CO poisoning associated with consumer products", the 20-foot generator rule and the winter fire and CO safety materials. Its month figure lives on a different CPSC page, the 2023 release below.
2. CDC, CO Poisoning Prevention . More than 400 unintentional deaths a year, more than 100,000 emergency department visits and more than 14,000 hospitalizations.
3. U.S. Consumer Product Safety Commission (CPSC), New CPSC Report Shows Upward Trend in Carbon Monoxide (CO) Fatalities (2023) . CPSC on the same seasonal shape, over a different population: "Most CO deaths occur in the colder months of the year, with more than half of the deaths occurring during the four cold months of November, December, January and February." An estimated 250 consumer-product CO deaths in 2019, the highest year in the 2009 to 2019 report, with engine-driven tools the largest category.
4. CDC, MMWR QuickStats, Deaths from Unintentional Carbon Monoxide Poisoning, by Month and Year, United States, 2010-2015 . Where the 36 per cent on this page comes from, in CDC's words: "In 2015, a total of 393 deaths resulting from unintentional carbon monoxide poisoning occurred, with 36% of the deaths occurring in December, January, or February." Over 2010 to 2015 the winter months carried the highest count every year.
5. USFA/FEMA, Carbon Monoxide . "More than 150 people in the United States die every year from accidental nonfire-related CO", attributed by USFA to CPSC, with the alarm guidance and free materials.
6. Ready.gov, Winter Safety . FEMA's winter readiness page, which puts CO prevention beside the heating advice that causes it: heat your home safely, and open a window slightly when using an alternative heat source.
7. NFPA, Carbon Monoxide Safety . NFPA's consumer guidance, alarms "in a central location outside each sleeping area and on every level", plus its own downloadable toolkit, "Keeping Your Community Safe with Carbon Monoxide Alarms". The toolkit is NFPA's, not a joint one with CPSC.
8. American Red Cross, CO Preparedness . The Red Cross household CO checklist, downloadable in English and Spanish, and the clearest statement of the alarm sounds: "Smoke alarms typically make three fast beeps ... A carbon monoxide alarm makes four fast beeps."
9. CDC MMWR, Hurricane Irma CO Deaths . Of 129 confirmed Hurricane Irma-related deaths, 16 (12.4 per cent) were carbon monoxide poisonings and only 11 (8.5 per cent) were directly related to the storm. The generators killed more people than the hurricane did.
10. American Lung Association, CO Safety . Winter-specific tips. Its figure, "more than 50,000 people visit emergency rooms" a year with "about 430 of these visits" fatal, is an older count than the more than 100,000 CDC publishes now.
11. U.S. Consumer Product Safety Commission (CPSC), Safety Standard for Portable Generators, 88 FR 24336 (20 April 2023) . What a CO-sensing generator actually has to do, which matters in the two seasons this check flags for generator use: UL 2201 shuts the engine off at 150 ppmv on a 10-minute rolling average or 400 ppmv instantaneously, and caps the weighted emission rate at 150 g/h.
12. Minnesota Dept. of Health, Carbon Monoxide (CO) Poisoning in Your Home . A state health department view of the same seasons, and the source of a third distinct placement distance: Minnesota Statute 299F.50 requires that every home have at least one operational CO alarm within 10 feet of every room legally used for sleeping, against Illinois's 15 feet and NFPA 72's 21 feet.