Winter can be a wonderful time in East Tennessee! If you like cold weather, cozy fires, and hot chocolate, you’ll love this time of year. Winter also brings, or increases the risk of, house fires and carbon monoxide poisoning. By taking simple steps to ensure your home and occupants are properly protected, you can enjoy a safe and happy winter season!
Carbon monoxide (CO) is a colorless, odorless, poisonous gas that forms from incomplete combustion of fuels, such as natural or liquefied petroleum gas, oil, wood or coal.
Facts and Figures
- Each year in the U.S., approximately 500 deaths are caused by non-fire-related carbon-monoxide poisoning.
- Most CO exposures occur during the winter months, especially in December and in January. The peak time of day for CO exposure is between 6 and 10 p.m.
- Many experts believe that CO poisoning statistics understate the problem. Because the symptoms of CO poisoning mimic a range of common health ailments, it is likely that a large number of mild to mid-level exposure is never identified, diagnosed, or accounted for in any way in carbon monoxide statistics.
- Out of all reported non-fire carbon-monoxide incidents, 89% or almost nine out of 10 of them take place in a home.
Physiology of Carbon Monoxide Poisoning
When CO is inhaled, it displaces the oxygen that would ordinarily bind with hemoglobin, a process the effectively suffocates the body. CO can poison slowly over a period of several hours, even in low concentrations. Sensitive organs, such as the brain, heart and lungs, suffer the most from a lack of oxygen.
High concentrations of carbon monoxide can kill in less than five minutes. At low concentrations, it will require a longer period of time to affect the body. Exceeding the EPA concentration of 9 parts per million (ppm) for more than eight hours may have adverse health affects. The limit of CO exposure for healthy workers, as prescribed by the U.S. Occupational Health and Safety Administration (OSHA), is 50 ppm.
Potential Sources of Carbon Monoxide
Any fuel-burning appliances that are malfunctioning or improperly installed can be a source of CO, such as the:
- stove and oven;
- water heater;
- clothes dryer;
- room/space heater;
- fireplace and wood stove;
- gas and charcoal grill;
- auto and boat engines;
- clogged chimney or flue;
- power tools that run on fuel, such as a gasoline-powered lawnmower; and
- certain types of swimming pool heaters.
CO Detector Placement
CO detectors can monitor exposure levels, but do not place them:
- directly above or beside fuel-burning appliances, as appliances may emit a small amount of carbon monoxide upon start-up;
- within 15 feet of heating and cooking appliances, or in or near very humid areas, such as bathrooms;
- within 5 feet of kitchen stoves and ovens, or near areas locations where household chemicals and bleach are stored (store such chemicals away from bathrooms and kitchens, whenever possible);
- in the garage, kitchen, furnace room, or in any extremely dusty, dirty, humid, or greasy areas;
- in direct sunlight, or in areas subjected to temperature extremes. These include an unconditioned crawlspace, unfinished attic, un-insulated or poorly insulated ceilings, and porches;
- in turbulent air near ceiling fans, heat vents, air conditioners, fresh-air returns, or open windows. Blowing air may prevent carbon monoxide from reaching the CO sensors.
Do place CO detectors:
- within 10 feet of each bedroom door and near all sleeping areas, where it can wake sleepers. The Consumer Product Safety Commission (CPSC) and Underwriters Laboratories (UL) recommend that every home have at least one carbon-monoxide detector for each floor of the home, and within hearing range of each sleeping area;
- on every floor of the home, including the basement;
- near, but not directly above, combustion appliances, such as furnaces, water heaters, and fireplaces, and in the garage; and
- on the ceiling in the same room as permanently installed fuel-burning appliances, and centrally located on every habitable level, and in every HVAC zone of the building. This rule applies to commercial buildings.
In North America, some national, state and local municipalities require installation of CO detectors in new and existing homes, as well as commercial businesses, among them: Illinois, Massachusetts, Minnesota, New Jersey, Vermont and New York City, and the Canadian province of Ontario. Installers are encouraged to check with their local municipality to determine what specific requirements have been enacted in their jurisdiction.
How can I prevent CO poisoning?
- Purchase and install carbon monoxide detectors with labels showing that they meet the requirements of the new UL standard 2034 or Comprehensive Safety Analysis 6.19 safety standards.
- Make sure appliances are installed and operated according to the manufacturer’s instructions and local building codes. Have the heating system professionally inspected by Pinpoint Home Inspections and serviced annually to ensure proper operation. The inspector should also check chimneys and flues for blockages, corrosion, partial and complete disconnections, and loose connections.
- Never service fuel-burning appliances without the proper knowledge, skill and tools. Always refer to the owner’s manual when performing minor adjustments and when servicing fuel-burning equipment.
- Never operate a portable generator or any other gasoline engine-powered tool either in or near an enclosed space, such as a garage, house or other building. Even with open doors and windows, these spaces can trap CO and allow it to quickly build to lethal levels.
- Never use portable fuel-burning camping equipment inside a home, garage, vehicle or tent unless it is specifically designed for use in an enclosed space and provides instructions for safe use in an enclosed area.
- Never burn charcoal inside a home, garage, vehicle or tent.
- Never leave a car running in an attached garage, even with the garage door open.
- Never use gas appliances, such as a range, oven or clothes dryer to heat your home.
- Never operate un-vented fuel-burning appliances in any room where people are sleeping.
- During home renovations, ensure that appliance vents and chimneys are not blocked by tarps or debris. Make sure appliances are in proper working order when renovations are completed.
- Do not place generators in the garage or close to the home. People lose power in their homes and get so excited about using their gas-powered generator that they don’t pay attention to where it is placed. The owner’s manual should explain how far the generator should be placed from the home.
- Clean the chimney. Open the hatch at the bottom of the chimney to remove the ashes. Hire a chimney sweep annually.
- Check vents. Regularly inspect your home’s external vents to ensure they are not obscured by debris, dirt or snow.
Carbon monoxide is a dangerous poison that can be created by various household appliances. CO detectors must be placed strategically throughout the home or business in order to alert occupants of high levels of the gas.
A smoke alarm, also known as a smoke detector, is a device that detects smoke and issues an audible sound and/or a visual signal to alert residents to a potential fire.
Facts and Figures
According to the Consumer Product Safety Commission:
- Although most newer homes have smoke alarms, about one-third of all deaths in house fires in 2011 occurred in homes that lacked working smoke alarms.
- Older homes are more likely to lack an adequate number of smoke alarms because they were built before requirements increased.
- In 23% of home fire deaths, smoke alarms were present but did not sound. Sixty percent of these failures were caused by the power supplies having been deliberately removed due to false alarms.
- Every year in the United States, about 3,000 people lose their lives in residential fires. Most of these deaths are caused by smoke inhalation, rather than as a result of burns.
Smoke Alarm Types
Ionization and photo-electric are the two main designs of smoke detectors. Both types must pass the same tests to be certified to the voluntary standard for smoke alarms, but they perform differently in different types of fires. Detectors may be equipped with one or both types of sensors — known as dual-sensor smoke alarms — and possibly a heat detector, as well.
These sensors are described as follows:
- Ionization smoke sensors are the most common and economical design and are available at most hardware stores. They house a chamber sided by small metal plates that irradiate the air so that it conducts electricity. When smoke enters the chamber, the current flow becomes interrupted, which triggers an alarm to sound. These sensors will quickly detect flaming-type fires but may be slower to react to smoldering fires.
- Photo-electric smoke sensors use a light-sensitive photocell to detect smoke inside the detector. They shine a beam of light that will be reflected by smoke toward the photocell, triggering the alarm. These sensor types work best on smoldering fires but react more slowly to flaming fires. They often must be hard-wired into the house’s electrical system, so some models can be installed only in particular locations.
While heat detectors are not technically classified as smoke detectors, they are useful in certain situations where smoke alarms are likely to sound false alarms. Dirty, dusty industrial environments, as well as the area surrounding cooking appliances, are a few places where false alarms are more likely and where heat detectors may be more useful.
Individual authorities having jurisdiction (AHJs) may have their own requirements for smoke-alarm placement, so homeowners can check with their local building codes if they need specific instructions. The following guidelines, however, can be helpful.
Smoke alarms should be installed in the following locations:
- on the ceiling or wall outside of each bedroom;
- in the basement, preferably on the ceiling near the basement stairs;
- in the garage, due to all the combustible materials commonly stored there;
- on the ceiling or on the wall, with the top of the detector between 6 to 12 inches from the ceiling; and/or
- in each story within a building, including basements and cellars, but not crawlspaces or uninhabited attics.
Smoke alarms should not be installed in the following locations:
- near heating or air-conditioning supply and return vents;
- near a kitchen appliance;
- near windows, ceiling fans or bathrooms equipped with a shower or tub;
- where ambient conditions, including humidity and temperature, are outside the limits specified by the manufacturer’s instructions;
- within an unfinished attic or garage, or in other spaces where temperatures can rise or fall beyond the limits set by the manufacturer;
- where the mounting surface could become considerably warmer or cooler than the rest of the room, such as an inadequately insulated ceiling below an unfinished attic; or
- in dead-air spots, such as the top of a peaked roof or a ceiling-to-wall corner.
Power and Interconnection
Power for the smoke alarms may be hard-wired directly into the building’s electrical system, or it may come from just a battery. Hard-wired smoke detectors are more reliable because the power source cannot be removed or drained, although they will not function in a power outage unless they also have batteries for backup. Battery-operated units often fail because the battery can be easily removed, dislodged or drained, although these units can be installed almost anywhere. Older buildings might be restricted to battery-powered designs, while newer homes generally offer more options for power sources. If possible, homeowners should install smoke alarms that are hard-wired with a battery backup, especially during a renovation or remodeling project.
Smoke alarms may also be interconnected so that if one becomes triggered, they all sound in unison. Interconnected smoke alarms are typically connected with a wire, but new technology allows them to be interconnected wirelessly. The National Fire Protection Agency requires that smoke alarms be protected by arc-fault circuit interrupters (AFCIs).
- Parents should stage periodic night-time fire drills to assess whether their children will awaken from the alarm and respond appropriately.
- Never disable a smoke alarm. Use the alarm’s silencing feature to stop nuisance or false alarms triggered by cooking smoke or fireplaces.
- Test smoke alarms monthly, and replace their batteries at least twice per year. Change the batteries when you change your clocks for Daylight Saving Time. Most models emit a chirping noise when the batteries are low to alert the homeowner that they need replacement.
- Smoke alarms should be replaced when they fail to respond to testing, or every 10 years, whichever is sooner. The radioactive element in ionization smoke alarms will decay beyond usability within 10 years.
- Smoke detectors should be replaced if they become damaged or wet, are accidentally painted over, are exposed to fire or grease, or are triggered without apparent cause.
- Note the sound of the alarm. It should be distinct from other sounds in the house, such as the telephone, doorbell and pool alarm.