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Smoke Alarms and CO Detectors: What You Should Know
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Thank you for your interest in Smoke Alarm and Carbon Monoxide (CO) Detector Safety! Please use this information to learn more about smoke alarms and CO detectors and where they should be located.
Smoke alarms and CO detectors are each an integral part of home safety. Arguably two of the most important inventions in the last 50 years, the household smoke alarm and the CO detector have the ability to alert you and anyone in your household to a potential emergency. This alert can provide you and your family with enough time to exit to safety. Ensuring the alarms are working is one of the most important parts of household safety planning.
See a few FAQs we at the Hanover Fire Department receive when we talk with folks about smoke alarms and CO detectors.
- Where should smoke alarms be installed?
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According to the NH State Fire Marshal, as well as the National Fire Protection Association (NFPA), "install smoke alarms inside each bedroom, outside each sleeping area and on every level of the home, including the basement." This applies to all single-family dwellings, multi-unit dwellings, and rental units.
- Here is an infographic from the NFPA to help visualize where to locate your Smoke Alarms
- Informational Bulletin (PDF) from the NH State Fire Marshal, Smoke Alarm Device Requirements in Dwellings
- Additional guidelines from the NFPA for proper smoke alarm installation
- Where should Carbon Monoxide (CO) detectors be installed?
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For each individual dwelling unit (house, apartment, rental unit, etc.) CO detectors shall be installed in a central location outside each sleeping area and on every occupiable level of the home, including the basement.
- Additional information from the NFPA on Carbon Monoxide detectors
- Additional information from the EPA about CO alarms
The EPA recommends installing wall-mounted CO detectors about 5 feet from the floor.
- How do I know if my alarm is working?
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Smoke alarms and CO detectors should be tested every month. Simply press the button and listen. (Protect your hearing, the alarm will be loud!)
- How do I know if my alarm is detecting these dangers effectively?
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Smoke alarms and CO detector components will deteriorate over time. Smoke alarms can only be expected to work effectively within 10 years of their Date of Manufacture (DOM). Carbon Monoxide detectors can only be expected to work effectively within 7 years of their DOM. The DOM can be found printed or stamped on the back of the device itself. If the device is a smoke alarm more than 10 years old or a CO detector more than 7 years old, it must be replaced and should not be expected to function properly. Devices should also be clean of dust or cobwebs, and they should never be painted or covered with anything: cloth, plastic, stickers, etc. – this could defeat their functional ability.
- Fire Safety Checklist from FEMA and the US Fire Administration (PDF)
This is a great resource for homeowners and renters alike to ensure their home is safe from easily avoidable fire hazards. - Additional resource for household fire safety information (PDF)
- Fire Safety Checklist from FEMA and the US Fire Administration (PDF)
- What is the best smoke alarm choice for my home?
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This one will require a little explanation, as there are several factors that may influence your choice:
- Internal components: Smoke alarms available in the U.S. contain two different smoke sensing technologies, ionization and photoelectric. Both are independently tested and certified to be effective at detecting smoke. However, one is better at detecting fast-flame fires (ionization) and the other is better at detecting smoldering fires (photoelectric). The State of Vermont requires all new construction (PDF) to have photoelectric smoke alarms installed. New Hampshire allows the installation of either photoelectric or ionization smoke alarms (PDF). There are devices available that use both sensing technologies, which may provide the best of both worlds. If you must choose, however, research has shown that photoelectric sensors are better for detecting common household fires and they are less susceptible to nuisance activations from cooking, steam, etc. When it comes time to replace your alarms, choose photoelectric first, or a combination unit second.
- Battery choices: All smoke alarms are required to have a battery backup. With new battery technologies, there are now self-contained smoke alarms that offer a 10-year life expectancy without having to ever change the battery. These options offer great convenience but come at an increased cost. A 10-year battery is the best option if it works for you and your family.
- Interconnected smoke alarms are best. In some older homes, smoke alarms were not part of the original construction, and connecting a network of smoke alarms in a house can be very expensive if a broader renovation is not already underway. New technology, again, has come to the rescue offering the ability to interconnect a home's smoke alarms through Wi-Fi. If smoke alarms are interconnected, when one sounds, they all sound. This is best for alerting residents to the alarm.
- Alert options: There are now alarms that do more than just beep! Options include strobe lights and vibration alerts (for the hard-of-hearing), and many manufacturers offer alarms that provide a verbal alert, which has been shown to be more effective at waking children. Since half of all home fires occur between the hours of 11 pm and 7 am, this functionality may be the best option for alarms located in children's bedrooms.
- What is the best Carbon Monoxide detector choice for my home?
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Carbon Monoxide detectors are all the same on the inside, so there is less of a debate here. CO detectors are available in several different varieties, and they can have additional functionality, like explosive gas detection in addition to CO detection. They can be wall-mounted, outlet-mounted, stand-alone units, or included as part of a dual-sensor smoke and CO alarm. Heat rises, and CO is associated with heating appliances, as it is most commonly encountered as a product of incomplete combustion. Additionally, on a molecular level, CO is slightly lighter than air. The EPA recommends wall-mounted units about 5 feet from the floor. But ultimately, the best CO detector for you and your family is one that works, has fresh batteries, and that is less than 7 years from its date of manufacture.
Thank you for reading through to the end here. If you are left with any questions or concerns, please do not hesitate to email us at the Hanover Fire Department or call 603-640-3399. Be well and be safe!