Carbon monoxide (CO) poisoning is in the news. Earlier this winter, there were a couple of schools that were evacuated because of high levels of Carbon Monoxide. Recently, here in New England we lost 3 of 4 members of a local family, a manager of a Legal Seafood restaurant and we had the evacuation of a hotel because of high Carbon Monoxide coming from their kitchens.

The laws regarding CO detectors typically specify that they need to be installed where any fossil burning appliances are located and near sleeping areas. However CO can get into a building any number of ways: for instance, the Legal Seafood restaurant had a defective chimney and the gas leaked into the building. This type of incident was responsible for the creation of Vermont's CO Law.

So will the laws change? The answer is yes: they are constantly changing and you’re going to see that the need for CO detectors is going to spread from the bedroom to the boardroom. We are going to have to start looking for CO gas not just in the room adjacent to the garage, but also adjacent to the chimney or flu; not just within 10 feet of a sleeping area, but close to a classroom.

We've established that the requirements for CO detectors are only going to increase. Now you need to know what you are buying. There are 100's of choices for CO detectors out there. What are the features and benefits, why are some inexpensive and others cost so much? First, let's take a look at what is important in a CO detector?

Ease of Installation

What is the easiest CO detector to install?
We have the First Alert (BRK) models CO600B and CO605B. These units simply plug into a standard wall socket and you're off and running. They are relatively inexpensive and have a 5 year warranty. The CO605B has a 9 Volt Battery as a backup in case you lose power or someone unplugs the unit to run the vacuum.

Next are the Battery Operated units. These have the advantage that they can be put anywhere, not just where a plug may be. These units are the First Alert CO400B, the Air Products APC-9V-CO and APC-9V-CO-S (combo CO and Smoke). We can also recommend BRK's SC05BN and SC07B (which has a Voice Alert feature).


Simply put, a CO detectors needs to detect Carbon Monoxide; or in the case of a combo unit, CO and Smoke.

Battery operated devices are great until the battery dies at 3 AM and the device begins beeping every 3 or 4 minutes. How many times have you heard reports of fire fatalities where they said there were smoke detectors installed, but no batteries?

120 Volt Plug-in Devices are limited by the location of the AC sockets and they are not interconnected. Most battery-only or 120 Volt with battery backup devices that are of the "Hardwired" variety (not plug in) are interconnect able. Interconnected simply means that if a CO detector in the basement senses CO and activates, it will activate all of the detectors that are wired together and notify everyone in the residence of the emergency. In many cases, many models made by the same manufacturer will "talk" to each other. For example, if you have 3 BRK Smoke Alarms, 2 Combo Smoke/CO Alarms and 2 CO detectors, they will all interconnect and notify the occupants of either a fire (coded "3") or Carbon Monoxide (coded "4").

The last type of CO detector is the system detector. System detectors are not plug-in or battery operated. System detectors are hardwired into a fire or combination fire/burglar panel or HVAC controller. System devices operate on either 12 or 24 VDC and have either a set of contacts that initiate an alarm in the control panel or have an analog output which changes as the levels of CO in the room change.

The latter are used in sophisticated HVAC systems that initiate purge fans at low levels and evacuation signals as the CO rises to dangerous levels. As a note of interest, the Gentex CO1209F 120V hardwired detector has relay outputs for connection to alarm systems, fans, etc... all of these relay connections will function when the main power goes out. Not all units with relays can claim that.

In Summary

So what CO detector is right for you? Not all applications are the same, which is why all the different styles of detectors are successful in the marketplace. Let me give you a few guidelines:

  • Dollars are usually the bottom line in most of these decisions. Let me ask you; would you accept a heart transplant from the lowest bidder? Don't let price be the highest priority when choosing life safety devices.
  • Ease of installation: plug-in types or battery-only devices do work (they wouldn't be on the market if they didn't). However they have limitations as to placement and in the case of the battery-operated detectors, maintenance issues.
  • 120 volt devices with battery backup is what most Fire Departments are requiring; they are dependable, placed where the detection is required and can be interconnected so that the individual detectors act like a single system in the event of an emergency. They should be installed by a licensed electrician and you will need to make sure you have all compatible devices (for example, a BRK detector will not interconnect with a Gentex detector).
  • The final and critically important issue is lifespan. Smoke alarms can last a long time, although the codes are specifying a 10 to 12 year service life of smoke alarms. CO detectors last as little as 3 and as many as 7 years. Make sure you ask for the lifespan or warranty period for any CO detector you purchase.
Part Number Description Voltage Battery Backup CO Smoke Interconnect End of Life Warranty Buy Link

Battery Operated Detectors
APC-9V-CO 9V Battery-Operated CO Detector, 5-Year Warranty 9V Battery NA X   NA 6 Yrs 5 Yrs Buy Now
APC-9V-CO-S 9V Battery-Operated Combination Smoke/CO Detector, 5-Year Warranty 9V Battery NA X X NA 6 Yrs 5 Yrs Buy Now
BR-CO400B First Alert CO400B Battery-Operated (9V) Carbon Monoxide Alarm 9V Battery NA X   NA 5 Yrs 5 Yrs Buy Now
BR-SC05BN First Alert SCO5CN Combination CO, P/E Smoke, Battery-Powered (AA) 2 AA Batteries NA X X NA 5 Yrs 5 Yrs Buy Now
BR-SC07B BRK SCO7B Battery-Operated Photoelectric Smoke/CO Combo Alarm with Voice 2 AA Batteries NA X X NA 5 Yrs 5 Yrs Buy Now

Hardwired Detectors
APC-120V-CO-S 120V AC Combination Smoke/CO Detector w/ Battery Backup, 5-Year Warranty 120VAC 9V Battery X X 12 Units 6 Yrs 5 Yrs Buy Now
BR-CO5120BN BRK CO5120BN 120V CO Detector w/Battery Backup 120VAC 9V Battery X   18 Units 5 Yrs 5 Yrs Buy Now
BR-SC9120B BRK SC9120B 120V Smoke/CO Detector w/Battery Backup 120VAC 9V Battery X X 18 Units 5 Yrs 5 Yrs Buy Now
GN-CO1209 Gentex CO1209, 120VAC/9VDC Single/Multiple Station CO Alarm 120VAC 9V Battery X   12 Units 5 Yrs 5 Yrs Buy Now
GN-CO1209F Gentex CO1209F, 120VAC CO Detector with 9V Battery Backup, Relay 120VAC 9V Battery X   12 Units 5 Yrs 5 Yrs Buy Now

Plug-in Detectors
BR-CO600B First Alert CO600B Plug-in Carbon Monoxide Alarm 120VAC NA X   NA 5 Yrs 5 Yrs Buy Now
BR-CO605B BRK CO605B, Plug-in CO Alarm with Battery Backup 120VAC 2 AA Batteries X   NA 5 Yrs 5 Yrs Buy Now

System Detectors
BK-CO1224T System Sensor CO1224T 4-wire CO Detector w/RealTest Technology 12/24VDC Alarm System X   NA 6 Yrs 3 Yrs Buy Now
BK-CO1224TR System Sensor CO1224TR 4-wire Round CO Detector w/RealTest Technology 12/24VDC Alarm System X   NA 6 Yrs 3 Yrs Buy Now
MA-CME1* Macurco CM-E1 Carbon Monoxide Detector, 9-32VDC, UL2075 12/24VDC Alarm System X   NA 7 Yrs 2 Yrs Buy Now
MA-CM6 Macurco CM-6 Carbon Monoxide Detector, Controller and Transducer 12/24 VDC 12/24VDC Alarm System X   NA 7 Yrs 2 Yrs Buy Now
PL-CO1224 Potter Electric CO-1224 CO Detector wtih Trouble Relay 12/24VDC Alarm System X   NA 6 Yrs 6 Yrs Buy Now

* The Macurco PS-12 allows the CM-E1 to be powered off of 120 VAC (with no battery backup).

If you need help choosing the right carbon monoxide detector for your application, please call us at 800-837-8175. We're always here to help.