Carbon Monoxide
STATE LAW REQUIRES CARBON MONOXIDE ALARM DETECTORS
The “Carbon Monoxide Alarm Detector Act” is a state law that requires all residences (Single family & Multi family dwelling units) to have carbon monoxide detectors installed. The law applies to both new and existing properties with few exceptions.
Carbon monoxide detectors need to be installed within 15 feet of each bedroom and may be DC battery, AC plug in with battery back up, or AC hard wired with battery back up.
WHAT IS CARBON MONOXIDE (CO) AND WHY DO I NEED A CARBON MONOXIDE DETECTOR?
Carbon monoxide is a colorless, odorless, tasteless and toxic gas produced as a by-product of combustion. Any fuel burning appliance, vehicle, tool or other device has the potential to produce dangerous levels of carbon monoxide gas. Examples of carbon monoxide producing devices commonly is use around the home include:
- Fuel fired furnaces (non-electric)
- Gas water heaters
- Fireplaces and wood stoves
- Gas stoves
- Gas dryers
- Charcoal grills
- Lawn mowers, snow blowers, and other yard equipment
- Automobiles
The Consumer Products Safety Commission (CPSC) reports that approximately 200 people per year are killed by accidental CO poisoning with an additional 5000 people injured. These deaths and injuries are typically caused by improperly used or malfunctioning equipment aggravated by improvements in building construction which limit the amount of fresh air flowing in to homes and other structures.
While regular maintenance and inspection of gas burning equipment in the home can minimize the potential for exposure to CO gas, the possibility for some type of sudden failure resulting in a potentially life threatening build up of gas always exists.
WHAT ARE THE MEDICAL EFFECTS OF CARBON MONOXIDE AND HOW DO I RECOGNIZE THEM?
Carbon monoxide inhibits the blood’s ability to carry oxygen to body tissues including vital organs such as the heart and brain. When CO is inhaled, it combines with the oxygen carrying hemoglobin of the blood to form carboxyhemoglobin. Once combined with the hemoglobin, that hemoglobin is no longer available for transporting oxygen. How quickly the carboxyhemoglobin builds up is a factor of the concentration of the gas being inhaled (measured in parts per million or PPM) and the duration of the exposure. Compounding the effects of the exposure is the long half-life of carboxyhemoglobin in the blood. Half-life is a measure of how quickly levels return to normal. The half-life of carboxyhemoglobin is approximately 5 hours. This means that for a given exposure level, it will take about 5 hours for the level of carboxyhemoglobin in the blood to drop to half its current level after the exposure is terminated.
THE FOLLOWING TABLE DESCRIBES THE SYMPTOMS ASSOCIATED WITH A GIVEN CONCENTRATION OF COHb.
| % COHb | Symptoms and Medical Consequences |
| 10% | No Symptoms |
| 15% | Mild Headache |
| 25% | Nausea and serious headache. Farily quick recovery after treatment with fresh air or oxygen. |
| 30% | Symptoms intensify with a potential for longer term effects especially in children, the elderly, pregnant women and victims of heart disease. |
| 45% | Unconsiousness. |
| 50% | Death. |
As can be seen from the above information, the symptoms vary widely based on exposure level, duration and the general health and age on an individual. Also note the one recurrent theme that is most significant in the recognition of carbon monoxide poisoning – headache, dizziness and nausea. These “flu-like” symptoms are often mistaken for a real case of the flu and can result in delayed or mis-diagnosed treatment. When experienced in conjunction with the sounding of a carbon monoxide alarm these symptoms are the best indicator that a potentially serious buildup of carbon monoxide exists. This comment will be returned to later.
WHAT ARE THE DIFFERENT TYPES OF CARBON MONOXIDE DETECTORS AND HOW DO THEY WORK?
There are a number of different types and brands of carbon monoxide detectors on the market today. They can be most easily characterized by whether they operate on household current or batteries. Underlying this, in most cases, is the type of sensor employed in the detectors operation. Detectors using household current typically employ some type of solid-state sensor which purges itself and resamples for CO on a periodic basis. This cycling of the sensor is the source of its increased power demands. Detectors power by batteries typically use a passive sensor technology which reacts to the prolonged exposure to carbon monoxide gas.
HOW MANY CARBON MONOXIDE DETECTORS SHOULD I HAVE AND WHERE SHOULD I PLACE THEM?
The Consumer Product Safety Commission recommends a detector on each floor of a residence. At a minimum, a single detector should be placed on each sleeping floor with an additional detector in the area of any major gas burning appliances such as a furnace or water heater. Installation in these areas ensures rapid detection of any potentially malfunctioning appliances and the ability to hear the alarm from all sleeping areas. In general carbon monoxide detectors should be placed high (near the ceiling) for most effective use. Detectors should also not be placed within five feet of gas fueled appliances or near cooking or bathing areas. Consult the manufacturers installation instructions for proper placement of a detector within a given area.
WHAT ARE THE MOST COMMON CAUSES OF CARBON MONOXIDE DETECTOR ALARMS?
There are many conditions which can cause a carbon monoxide to alarm. Most are preventable and few are actually life threatening. Ideally through proper placement of the detector and education of the users the number of preventable calls can be minimized and activation will only occur in the more serious situations.
Preventable causes of CO alarm activation and the recommended preventive action are as follows:
- Inadequate fresh air venting of the home.
- Running gas powered equipment or automobiles in a home or garage.
- Charcoal grilling in the home or garage.
- Malfunctioning appliances or equipment in the home.
- Malfunctioning or overly sensitive alarm.
Preventative Action
- Have a heating contractor install a fresh air makeup system in the home.
- Gas powered equipment or vehicles should never be operated within a home or garage, even if the garage door is open.
- Since most homes are typically at a lower pressure relative to the outside air, the gas can actually be drawn into the home.
- Charcoal grilling is a tremendous producer of carbon monoxide gas.
- Charcoal grills should never be operated in the home.
- All fuel burning appliances or equipment in the home need periodic inspection and preventative maintenance.
- While all fuel burning appliances will produce some CO gas, regular preventative maintenance can keep this to a minimum.
WHAT SHOULD I DO WHEN MY CARBON MONOXIDE DETECTOR GOES OFF?
First and foremost, stay calm. As mentioned previously most situations resulting in activation of a carbon monoxide detector are not life threatening and do not require calling 911. To determine the need to call 911, ask the following question of every one in the household:
“Does anyone feel ill? Is anyone experiencing the “flu-like” symptoms of
headache, nausea or dizziness?”
If the answer to the above by anyone in the household is true, evacuate the household to a safe location and have someone call 911. Failure to evacuate immediately may result in prolonged exposure and worsening effects from possible carbon monoxide gas. The best initial treatment for carbon monoxide gas exposure is fresh air.
If the answer to the above by everyone in the household is no, the likelihood of serious exposure is greatly diminished and one probably does not need to call 911. Instead, turn off any gas burning appliances or equipment, ventilate the area and attempt to reset the alarm. If the alarm will not reset or resounds, call a qualified heating and ventilating service contractor to inspect your system for possible problems. If at any time during this process someone begins to feel ill with the symptoms described above evacuated the household to a safe location and have someone call 911.
When initially calling 911 be prepared to provide the following information:
- Your address.
- The type of detector that is sounding.
- Whether or not anyone is feeling ill with 'flu-like' symptoms as previously described.
- Whether or not everyone has evacuated the residence.
- The reading on the detector ( if known or available).
