Carbon Monoxide: What You Need to Know

Oct. 27, 2008
As cities and state continue to pass carbon monoxide detector laws, the demand for these products is soaring

It’s late at night in the Smith household. Mr. Smith’s wife and young son are already asleep, and he’s just finished watching the 10 o’clock news. What he doesn’t know is that within the past 12 hours his water heater, which hasn’t been serviced in years, has started to leak large amounts of a poisonous gas: carbon monoxide.

Mr. Smith turns off the lights in his living room and heads up the steps to bed. He’s had a mild headache all evening, so he finally gives in and takes some aspirin. He doesn’t feel as steady as he usually does, but he figures that he just needs a good night’s rest. So he crawls into bed, sets his alarm, and within a few minutes drifts into sleep.

Unfortunately, nobody in Mr. Smith’s family survives the night.

While the above account is fictionalized, similar real-life stories happen every year; and as such, states are beginning to pass laws that require carbon monoxide detectors in buildings where people sleep. With a growing market for carbon monoxide detection, security dealers should understand the threat and know which new products can serve their customers’ needs.

Carbon monoxide (CO) is a gas comprised of a carbon atom bonded to an oxygen atom. CO is produced by the incomplete combustion of carbon-containing compounds such as gasoline, coal, oil, and wood. It is a common gas that can result from the use of engines, oil burners, open fires, gas fires, water heaters, and other appliances. The danger posed by CO is when it starts to accumulate in high concentrations, which can happen in areas that are improperly ventilated or with appliances that aren’t maintained and start leaking excessive amounts of the gas.

Furthermore, CO is colorless, odorless, and tasteless, which is why it’s also known as, “The Silent Killer.” Some symptoms that a person might experience before succumbing to CO poisoning include headache, nausea, dizziness, and shortness of breath. However, these symptoms are all fairly common and can be found in other ailments, such as the flu. Obviously, if ever you suspect high levels of carbon monoxide, get to fresh air immediately. Also, try to turn off the source of CO if possible.
“We would encourage all consumers to have CO detectors in their homes,” says Patty Davis, spokesperson, U.S. Consumer Products Safety Commission. She went on to explain that even homes that don’t have gas lines in them could be at risk from an attached garage (running car could leak CO into home) or from gas grills or generators used improperly inside a home (possibly during a power outage in the aftermath of a natural disaster such as a hurricane or blizzard).

When former American tennis star Vitas Gerulaitis died of carbon monoxide poisoning while sleeping in a friend’s guesthouse in 1994, the story was widely reported and CO alarms experienced a temporary boost in sales. However, states didn’t begin mandating the alarms by law.

In recent years, things have changed. As carbon monoxide tragedies have remained in the news and detectors have improved, more cities and states are moving to pass laws. A recent example was when Miami passed “Janelle’s Law” last year, requiring the installation of CO detectors in homes, rental units, hotels and motels. The law was named for Janelle Bertot, a Florida International University student who died from CO poisoning in 2004.

“In 2003, New York state was one of the larger states to first pass legislation to require CO alarms in homes, and since then a number of states have followed with some sort of variation of a law,” says Suzanne Turner, director of communications and marketing, Kidde R&C. “Some states may require new construction only—for example, Connecticut—while other states have passed more stringent and extensive laws to require both existing and new construction homes.”

Some state CO laws only require alarms in one- and two-family dwellings, while others require them in apartments, hotels, motels, and dormitories, adds Turner. “So we have seen a lot of variation of different types of laws that have passed across the country.”

“There is a strong regulatory trend mandating the installation of carbon monoxide detectors,” says Richard Roberts, carbon monoxide product manager, System Sensor. “In the past six years, 11 states—mostly in the northeast and large cities like New York, Chicago, Charlotte and St. Louis—have adopted ordinances requiring the installation of CO detectors. Several more states have pending legislation. These ordinances have aided the adoption of the CO detector in the market.”

Rick Cullwell, sales manager for fixed gas detection systems, 3M – Macurco, says that he really sees CO detectors becoming mainstream. “About ten years ago when I asked people at trade shows how many people had installed one, probably about 2 out of every 10 installers had put in a new carbon monoxide or gas detector,” he recalls. “Now when I ask those people about 6 to 8 out of every 10 people are doing that.”

Carbon monoxide detectors have made great strides in the past decade. Their sensors are becoming more reliable, and some now display CO levels for the user to monitor at anytime. Furthermore, manufacturers are starting to make CO detection products that hook up to fire and/or security panels and can be monitored by a central station.

“The system-connected CO market is in its infancy stage and is ready for significant growth,” says Roberts. “The market has grown 30% year-over-year for the past several years. With more and more states requiring carbon monoxide protection, we expect this strong growth to continue.”

Among the next-generation CO detectors that work with both fire and security panels is System Sensor’s CO1224. It has a built-in trouble relay and SEMS terminals for wiring supervision, allowing it to calculate CO levels and quickly communicate the info to the panel.

Macurco, which was recently acquired by 3M, also has a new CO detector on the market. “The CM-S1 is our newest unit,” says Cullwell. “It’s the only unit on the market right now that has been UL-listed to be flush mount over a single gang box. It’s 12 to 24 volts, so it will work with a fire or burglar alarm panel as well as relay outputs which will tie back and be monitored by the system.”

The Kidde 900-0114 is a unique combination smoke/CO detector. Also, Kidde’s CO alarms use a patented electrochemical sensor, called Nighthawk.

“We currently do not sell a unit that alone will work in a security system, but what we do offer is a relay device which allows for a Kidde smoke or carbon monoxide or combination smoke/CO unit to work in conjunction with an existing security system,” explains Turner.
“The relay device will allow for a Kidde CO alarm (or a combination alarm) to work in conjunction with an existing security system,” she says.


First published in 1992, UL 2034 is the standard created by Underwriters Laboratory along with federal agencies and experts to ensure that carbon monoxide detection technology employed in a home actually detects dangerous levels of CO and properly alerts people in the vicinity.

UL 2034 has been revised three times (1995, 1998, and 2003), and a fourth revision is due this year. The changes expected in March 2007 include:

• CO alarms must prove their stability at a lower relative humidity. The new amendment would require testing at 10% +/- 3 relative humidity, which can often occur indoors during winter months.

• CO alarms with digital display screens must have a minimum accuracy level of +/-30% of the actual CO concentration.
The NFPA 720 is a standard for the installation of carbon monoxide warning equipment in dwelling units. Macurco is one of the manufacturers working with NFPA to come out with a new version of NFPA 720 which will focus on the commercial applications of carbon monoxide, says Rick Cullwell, sales manager for fixed gas detection systems, 3M – Macurco. Some of the issues the new version will specifically address include how the systems are monitored as well as yearly testing.