Safety Alarms

Photo illustration of smoke detector

LP-gas, carbon monoxide and smoke detectors must be maintained to provide uncompromised protection

Carbon monoxide (CO) exposure is the leading cause of poisoning deaths in America, according to the Centers for Disease Control and Prevention. Of the 364,000 residential fires in 2016, 50.3 percent were caused by cooking accidents and 9.6 percent were the result of heating mishaps, according to the U.S. Fire Administration. Motorhomes are not exempt from these disasters, and the industry employs LP-gas, smoke and CO detectors to prevent human tragedy in RV parks and while on the road.

There is a silver lining to all these adversities — the inherent compact space in an RV makes it more likely that you’ll be aware of emergencies more quickly. However, this can only happen if the motorhome’s safety systems are in good working order.

All RVs built in the last quarter century are equipped with smoke detectors and LP-gas detectors. At one time, carbon monoxide detectors were mandated only for RVs with generators or generator-ready compartments, but now all motorhomes are equipped with certified devices to protect against CO poisoning. Also, fire extinguishers and emergency exits are part of all safety systems and must be tested and maintained. Detectors have a 7-10 year maximum lifespan before they need to be replaced, depending on the type of device.

Let’s take a look at each of the hazards, along with their detectors.

This CO detector has a button to silence an alarm briefly.
The CO detector should be mounted on the ceiling outside the main sleeping area. This model (far left) has a button to silence an alarm briefly.

Carbon Monoxide

CO is produced when fuel is burned. LP-gas, gasoline or diesel-fired equipment in and around your RV creates CO. Most of the gas appliances vent to the outside; however, a blocked flue, exhaust pipe, or even a breeze in the wrong direction can bring CO inside the motorhome. Generators are frequent offenders, especially in tight quarters where the exhaust can flow from one motorhome to another. CO is colorless, odorless and kills by slowly replacing the oxygen in the blood at the cellular level. Early symptoms are flu-like and include a headache, nausea, fatigue and dizziness. Eventually, the victim falls asleep and doesn’t wake up.

This is why CO detectors are now a mandatory fixture in all RVs. Most motorhomes will have separate CO and smoke detectors mounted on the ceiling. CO detectors generally have a 10-year lifespan from the time they are first activated. Most CO detectors have a sticker that indicates service and replacement dates. If it’s not filled out, then the manufacturing date starts the “clock.”

If the CO detector in your motorhome uses a battery, it should be replaced annually. Use only the type of battery recommended by the manufacturer. Changing the batteries can be an annual spring opener activity, or if you’re a full-timer, when you change the clocks (for daylight-saving time, if necessary). Many, but not all detectors have a low-battery and/or an end-of-life signal.

Photo of Atwood RV Propane Gase detector
The LED on this LP-gas detector turns red during an alarm and yellow for end-of-life. This detector can be surface-mounted, but it comes with the materials for flush-mounting, if desired. A convenient “Replace By” sticker is included.

If the CO alarm activates, immediately ventilate the RV and turn off all fuel-burning appliances until the culprit can be found. Many alarms have a function that temporarily silences the alarm. Never remove the battery while people are in the motorhome. The detectors have a safety feature that prevents the battery door from being closed when no battery(ies) is present. If anyone is having CO symptoms, call 911 immediately.


LP-Gas Detector

LP-gas, or propane, is used to fuel appliances in many motorhomes. It is a safe and stable fuel that is energy efficient when used correctly. The LP-gas system in a motorhome operates at 11 inches of water column, which is pretty low pressure. However, if propane is allowed to flow into a space, it can become a significant hazard. To combat this, propane has a distinctive odor, and LP-gas detectors are designed to provide a loud alert in the event of a leak, long before it can become a hazard.

Propane detectors in motorhomes are 12-volt DC powered and connected directly to the house batteries, in most cases. Some alarms are connected to an electric solenoid valve on the LP-gas tank that closes in the event of a power failure or during an alarm event. Others are simple alarms that activate in the presence of LP-gas. Since propane is heavier than air, propane detectors are always mounted near the floor.

Most LP-gas detectors have a five-to-seven-year lifespan before replacement becomes necessary. Unlike other detectors, the years are counted when the device is powered up, not from the date put in service. Many will have an end-of-life signal to indicate the need to replace the unit.

Photo showing production date stamps on the backs of old and new Dometic/Atwood LP-gas detectors.
Note the production date stamps on the backs of these old and new Dometic/Atwood LP-gas detectors. This detector will produce an alarm when it has reached its end of life, which is being powered for seven years.

If the LP-gas alarm sounds, leave the motorhome immediately, close the LP-gas tank valve and ventilate the interior. Be cognizant of any source of ignition, like light switches, which should not be turned on while vacating the interior. Most detectors have a feature that will temporarily silence the alarm. Sometimes other gases, like those from aerosol cans, can cause an alarm in the right concentrations. If you’re confident this is the cause, ventilate the area and silence the alarm.

Smoke Detectors

Everyone should be aware of smoke detectors mounted in motorhomes. The simple act of making toast can set them off … as can smoke from a campfire or outside grill. They can be annoying, but they will save your life in the event of a fire. All they require is a new battery every year. Hopefully, your motorhome came with a detector that has a silence button to help with the nuisance alarms. If it didn’t, consider replacing it.


Beyond the need for replacing the batteries with the ones specified for the devices, it is essential to keep detectors in top condition. Cleaning them is also necessary. A can of compressed air, like Falcon Dust Off ($13.59 for two cans on can be used to remove any dust or particulates from the inside of the detectors.

A Dometic 12-volt DC combination LP-gas and CO alarm for RVs.
Dometic also offers a 12-volt DC combination LP-gas and CO alarm for RVs.

Testing is imperative. Detectors should be tested when the RV comes out of storage, before each trip and weekly while living in the motorhome. Simply press the button and listen for the alarm.

As mentioned before, detectors must be replaced as directed by the manufacturer. It may be necessary to remove or dismount the detector to see the date stamp, but this process only takes a few seconds. Adding a sticker near the detector with the replacement date will make it easier to look up.

Consider upgrading or adding additional detectors as needs dictate. They can be found online or at a local home center.

These devices are present to protect the safety and health of you and your family. Maintenance and operation are your responsibility, and RV incidents are sporadic. Being prepared can make unusual incidents even less common.

More Information

Dometic Corp. | Kidde



  1. Our detectors went off suddenly on us and when we talked to the local RV dealer he told us they all have a 5 yr life span. Each was over 100.00 to replace. Would have been nice if we had known in advance.


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