If your home uses natural gas, or if you have a wood or gas fireplace,
you need a carbon monoxide detector. In fact, even if you have an all-electric
home, you might consider getting a detector if you use a backup general
or other carbon-fueled heat/power source. Inhaling too much carbon monoxide
(CO) gas can lead to poisoning and possibly death, so there's pretty good
reason to spend $35 on a carbon monoxide detector. In many municipalities,
they are required in rental units and/or in newly constructed homes.
Three are three main types of CO detectors: plug-in models plug directly
into an existing outlet with battery backup; you can also find models that
only use battery power. Lastly, you might see hardwired detectors in newly
constructed homes. Most owners of existing homes will opt for plug-in or
battery units, that are easier to install.
If you have a large home, you might consider interconnecting CO detectors.
Most hardwired systems are interconnecting; when one alarm picks up dangerous
levels of CO, all the alarms sound. We did find one model, the First Alert
Onelink, that's battery powered but that can also connect to other models
to perform this function. That's a benefit in big homes or homes with several
floors, where you might not hear an alarm sounding in a distant part of the
Lastly, some models combine a carbon monoxide detector with a smoke alarm.
While that's one way to cut down on the number of sensor gadgets in your
home, these models typically include just one of the two types of smoke-detector
sensors (experts say your home needs both types for the best protection).
Consider these tips when shopping for a carbon monoxide detector:
- Look for
the UL symbol on the packaging. UL-listed CO detectors meet product
safety standards set by the Underwriters Laboratory, an independent product
safety certification organization. These CO detectors sound an audible
alarm for CO levels of 150 parts per million (ppm) that remain for at least
10 minutes or CO levels that remain at 70 ppm for one hour. All UL-listed
carbon monoxide alarms must also have a manual silence button and sound
another alarm within six minutes when elevated levels of CO are still present.
- Get a detector with
a digital display. The display can alert occupants to rising CO levels
even before they trigger the alarm. A CO concentration of only 30 ppm
may harm heart patients, unborn babies and children, but most detectors
don't trigger an alarm until CO levels are 70 ppm or higher. A display
indicating no CO is present is also useful for determining whether a triggered
detector is merely malfunctioning.
- A strobe light warns the hearing
impaired. Some detectors include a strobe light
(or a strobe light can be bought separately and attached) so that someone
hearing impaired knows an alarm has been triggered.
- Purchase at least one
CO detector for each level of the home. Also install a CO detector
in the basement if a furnace or other fuel-burning appliance is housed
- Ideal placement is about head-height on a wall. That's because appliances
that produce carbon monoxide usually also produce heat -- so CO rises
with hot air in a room. Place CO detectors at the recommended distance
from steam sources (e.g., bathrooms and dishwashers), household chemicals
and other factors that can trigger false alarms. Position CO detectors
20 feet from all fuel-burning appliances because they emit some CO when
initially turned on. Installed CO detectors shouldn't be near windows or
ceiling fans, where ventilation might prevent them from sounding an alarm.
- Regularly check
that the CO detector is working properly. If your detector is hardwired
directly into your home's electrical system, you should test the unit
monthly. For battery-operated units, test the detector weekly and strive
to replace its battery at least once a year. You should totally replace
detectors every five years unless directed differently by the manufacturer.
- Consider a
test kit. Detectors have a button that test alarms, but they can't
mimic CO to verify the sensors are working. Detectagas (*Est. $22) is an
example of a kit that can be purchased to test these sensors. It comes
with an aerosol can of CO and a plastic bag that seals around the detector
and allows you to accurately test that the alarm sounds when a dangerous
level of CO is present.
- Do not connect plug-in units to
an electrical outlet that is controlled by a light
switch. If the
switch is turned off, the detector will begin draining the backup batteries.
This leads to frustrating low-battery alerts and requires replacing batteries