How high does a carbon monoxide detector be mounted

There’s a myth that carbon monoxide alarms should be installed lower on the wall because carbon monoxide is heavier than air. In fact, carbon monoxide is slightly lighter than air and diffuses evenly throughout the room.

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How high off the floor should a carbon monoxide detector be placed?
Do you mount carbon monoxide detector high or low?
Where should a carbon monoxide detector be installed?

According to the carbon monoxide guidelines of the National Fire Protection Association (NFPA 720, 2005 edition), all carbon monoxide alarms “shall be centrally located outside of each separate sleeping area in the immediate vicinity of the bedrooms,” and each alarm “shall be located on the wall, ceiling or other location as specified in the installation instructions that accompany the unit.”

Why CO alarms are often installed near the floor

Standalone carbon monoxide alarms are often placed low on the wall because they need to be plugged into an outlet that’s near the floor. CO alarms can also have a screen that shows the CO level and needs to be at a height where it’s easy to read.

Why you shouldn’t install a CO alarm near heating or cooking appliances

Also keep in mind not to install carbon monoxide detectors directly above or beside fuel-burning appliances, as appliances may emit a small amount of carbon monoxide upon start-up. A carbon monoxide detector should not be placed within fifteen feet of heating or cooking appliances or in or near very humid areas such as bathrooms.

For more information about carbon monoxide safety, visit the National Fire Protection Association.

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I've got a Carbon Monoxide (CO) detector (BRK CO250B, instruction sheet PDF) that I am looking to install in our house. All of the bedrooms are on the top level of our quad-level house, and I'm planning on installing it in the hallway.

The directions say that it can be either ceiling or wall mounted. I've looked around online, and I've seen various recommendations for what the ideal height is for the detector.

Some say ceiling mounted is best, because CO is lighter than air. (Combination smoke/CO detectors all get mounted here.)
Some say that a few feet below ceiling height is best, because a pocket of warm air may prevent the CO from getting all the way up to the level of the detector.
Some say that "bed height," or 2-3 feet off the floor is best, because that is where you are when you are sleeping.

What is the best height for CO detectors? Are there current recommended heights or best practices to use when installing these things?

asked May 21, 2015 at 1:03

Carbon monoxide detectors should be installed according to the instructions that accompanied the unit.

From Nest Protect's website:

There’s a myth that all carbon monoxide alarms should be installed lower on the wall because carbon monoxide is heavier than air. In fact, carbon monoxide is slightly lighter than air and diffuses evenly throughout the room.
According to the carbon monoxide guidelines of the National Fire Protection Association (NFPA 720, 2005 edition), all carbon monoxide alarms “shall be centrally located outside of each separate sleeping area in the immediate vicinity of the bedrooms,” and each alarm “shall be located on the wall, ceiling or other location as specified in the installation instructions that accompany the unit.”
Standalone carbon monoxide alarms are often placed low on the wall, but it’s not because they’re more effective at that height. It’s usually because they need to be plugged into an outlet near the floor or have a digital readout that can be easily read.

answered May 21, 2015 at 1:38

DoresoomDoresoom

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The Code says, “Carbon monoxide alarms shall be installed in each bedroom or within 15 feet outside each bedroom door. If bedrooms are located on separate floors, a carbon monoxide alarm shall be installed on each floor.” (See ICC 908.7.1)

In addition, it says, “it shall be installed in accordance with the manufacturer’s instructions.” (See 908.7.1.1) Maybe that’s why there is no consensus for mounting height.

Combination smoke and carbon monoxide alarms shall conform to both smoke detector location requirements and carbon monoxide alarm detector locations. (See 908.8)

answered Nov 23, 2019 at 18:39

Lee SamLee Sam

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I've been working as a service tech.for the last 20 yrs & in my opinion I would install it right under your thermostat, assuming that IT'S installed at the correct height which would be about 5 & a half ft.from the floor or about eye or face level, reason being is that carbon monoxide enters your blood stream by way of the air you breathe.If it's a plug in type (which is what I prefer) I would use the length of the cord as a guide line & avoid corners cause it's true that air in corners does get stagnant there due to friction. Keep in mind though, air is always moving because of 1 reason or another & it's not rocket science,it doesn't have to be perfect, close is good enough.

answered Jul 19, 2016 at 16:05

It is generally agreed that carbon mono-oxide (CO) diffused into the surrounding air well from some emission source(s) such as fuel-burning appliances. Everyone knows that CO is an invisible, odorless and tasteless gas. Among the symptoms of CO poisoning are headache and drowsiness and others, but in the extreme exposure could lead to heart and lung failure, brain damage and/or death (and might not necessarily be in this order.)

As I read a lengthy 'FIRST ALERT User's Manual' for the CO detector Model CO1210 which conforms to UL 2034 Standard, I want to highlight a few basic warnings and cautions: This model "is intended for use in ordinary indoor locations of family living units." Its battery's service life may last up to 10 years. Since I live in an apartment, the warning posted on this CO Alarm/detector is appropriate for me: "This CO Alarm is designed for use inside a single-family home or apartment. It is not meant to be used in common lobbies, hallways, or basements of multi-family buildings unless . . . ."

There seem to be no mention of a recommended height (from the floor) for installing this CO detector Model CO1210, but let it be placed at least 20 feet (or 6 meters) away from an existing fuel-burning source or a furnace. However, there is a caution for mounting on table top or event for a wall, keep it at a height of 3 feet or less from the floor so as to minimize damage to the unit if it was knocked down accidentally.

answered Mar 2, 2020 at 17:39

Every single "expert"internet answer to this question, lists a different installation height, often with conflicting information about the reasons for it. If you followed all the instructions, you'd need 40 detectors, strung out all over a wall, at different heights. I intend to call my nearest big city fire department, and ask for the fire safety information officer. I trust none of the "expert" answers I see on the internet.

answered Dec 11, 2019 at 1:43

How high off the floor should a carbon monoxide detector be placed?

In order to ensure that your home has maximum protection, it's important to have a CO detector on every floor. Five feet from the ground. Carbon monoxide detectors can get the best reading of your home's air when they are placed five feet from the ground. Near every sleeping area.

Do you mount carbon monoxide detector high or low?

Standalone carbon monoxide alarms are often placed low on the wall because they need to be plugged into an outlet that's near the floor. CO alarms can also have a screen that shows the CO level and needs to be at a height where it's easy to read.

Where should a carbon monoxide detector be installed?

At a minimum, industry experts recommend a CO alarm be installed on each level of the home -- ideally on any level with fuel burning appliances and outside of sleeping areas. Additional CO alarms are recommended 5-20 feet from sources of CO such as a furnace, water heater or fireplace.