Carbon monoxide (CO) poisoning is a leading cause of unintentional poisoning deaths in the United States. CO gas is odorless and colorless; it is produced anytime a fossil fuel is burned. Carbon Monoxide poisoning is usually undetectable until exposure results in injury or death. It has been the cause of approximately 15,000 emergency department visits and nearly 500 deaths annually in the United States (Centers for Disease Control, Morbidity and Mortality Report, 1/21/05 and 12/21/07).
Most CO exposures occur at home and most involve females, children under 17 years, and adults aged 18-44 years; however, men and adults 65 years and older are more likely to die from Carbon Monoxide poisoning than other persons. The higher rate for men has been attributed to high-risk behaviors, such as working with fuel-burning tools or appliances. The higher rate among older persons has been attributed to the likelihood of older adults mistaking symptoms of CO poisoning for other conditions (e.g., influenza-like illnesses).
Effects of CO Poisoning
The following chart from Wikipedia’s Carbon Monoxide Poisoning entry identifies the symptoms and effects of CO poisoning based on concentration in parts per million:
|35 ppm (0.0035%)||Headache and dizziness within six to eight hours of constant exposure|
|100 ppm (0.01%)||Slight headache in two to three hours|
|200 ppm (0.02%)||Slight headache within two to three hours; loss of judgment|
|400 ppm (0.04%)||Frontal headache within one to two hours|
|800 ppm (0.08%)||Dizziness, nausea, and convulsions within 45 min; insensible within 2 hours|
|1,600 ppm (0.16%)||Headache, tachycardia, dizziness, and nausea within 20 min; death in less than 2 hours|
|3,200 ppm (0.32%)||Headache, dizziness and nausea in five to ten minutes. Death within 30 minutes.|
|6,400 ppm (0.64%)||Headache and dizziness in one to two minutes. Convulsions, respiratory arrest, and death in less than 20 minutes.|
|12,800 ppm (1.28%)||Unconsciousness after 2–3 breaths. Death in less than three minutes.|
Symptom severity depends on both the CO level and the length of exposure. With slowly-developing residential CO problems, occupants and/or physicians can mistake mild to moderate CO poisoning symptoms for the flu, which sometimes results in tragic deaths. For rapid onset, high level CO exposures (e.g., associated with use of generators in residential spaces), victims can quickly become mentally confused and lose muscle control without having first experienced milder symptoms. They are likely to die if not discovered and rescued.
For those who survive acute Carbon Monoxide poisoning, there may be after-effects such as short-term memory loss, partial blindness and/or depression in as many as half the victims.
Chronic exposure to low levels of carbon monoxide can cause symptoms like persistent headaches, lightheadedness, depression, and confusion. Usually once removed from exposure to carbon monoxide, these symptoms are resolved. However, one case noted permanent memory loss and learning problems after a 3-year exposure to relatively low levels of carbon monoxide from a faulty furnace.
Research indicates that long-term exposure to carbon monoxide carries the greatest risk to those with coronary heart disease and to women who are pregnant.
A Workplace Hazard
Although Carbon Monoxide poisoning is often thought of as a home-related risk, every year workers die from CO exposure, usually while using fuel-burning equipment and tools in buildings or semi-enclosed spaces without adequate ventilation.
Carbon monoxide is present in fuel combustion fumes produced by vehicle exhaust, furnaces, portable generators, power washers, fire places, charcoal grills, marine engines, forklifts, gas water heaters, and kerosene heaters.
When workers use exhaust-producing equipment in sealed indoor spaces, carbon monoxide exposure can bring on everything from headaches, dizziness, and drowsiness to nausea, vomiting, coma, and death.
Preventing CO Poisoning at Work
The Consumer Product Safety Commission recommends the following to prevent CO poisoning:
- Have the heating system professionally inspected 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 proper knowledge, skill and tools. Always refer to the owner’s manual when performing minor adjustments or 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.
- Install a Carbon Monoxide alarm that meets the requirements of the current UL 2034 safety standard. A CO alarm can provide some added protection, but it is no substitute for proper use and upkeep of appliances that can produce CO. Install a CO alarm in the hallway near every separate sleeping area of the home. Make sure the alarm cannot be covered up by furniture or draperies.
- 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 ranges, ovens, or clothes dryers to heat your home.
- Never operate unvented fuel-burning appliances in any room where people are sleeping.
- Do not cover the bottom of natural gas or propane ovens with aluminum foil. Doing so blocks the combustion air flow through the appliance and can produce CO.
- 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 complete.
If home Carbon Monoxide detectors were as commonplace as smoke detectors, many lives would be saved and permanent disabilities prevented. That is why a growing number of local and state governments are requiring the installation of CO detectors in single and multi-family housing, and some commercial enterprises.
Massachusetts was among the earliest adopters of CO detector requirements when, on November 4, 2005, Governor Mitt Romney signed “Nicole’s Law”, named after 7-year old Nicole Garofalo who died on January 28, 2005 after her Plymouth home filled with deadly amounts of carbon monoxide four days earlier. The furnace vents had been blocked by snow during a power outage.
Illinois passed the Carbon Monoxide Detector Act in 2007. Unfortunately, Missouri is one of 15 states that have no home CO detector requirements.