Smoke detectors are a life-saving device that should be in everyone’s home. You may not know that your smoke detectors have an expiration date—10 years for smoke detectors and 5 to7 years for combination smoke and carbon monoxide detectors. So how do you dispose of an expired smoke detector?
The answer to this question depends on the type of smoke detector. There are two types of smoke detectors: ionizing and photoelectric.
Ionizing smoke detectors use a tiny amount of a radioactive isotope, Americium 241, and electrically charged plates to detect smoke. When smoke enters the detector, it stops the flow of ions between the two electrically charged plates, causing the alarm to sound. Ionizing smoke detectors are best at detecting flaming fires.
Photoelectric smoke detectors contain a light sensor and a light aimed away from the sensor. When smoke enters the detector, the light is reflected off the smoke and onto the light sensor, causing the alarm to sound. Photoelectric smoke detectors are best at detecting smoldering fires.
There are also dual sensors which contain both types of detectors in one unit. You can identify the type of smoke detector you have by taking it off of the wall or ceiling and looking at the back. If you see a radioactive symbol (pictured to the right), then you have an ionizing or dual sensor smoke detector. Also on the back of the smoke detector is the manufacture date, which you can use to determine the expiration date.
Smoke detectors are not accepted at Montgomery County household hazardous waste or E-waste recycling events or drop-off locations. Photoelectric smoke detectors can be thrown in your household trash after removing the battery (you can read our article on recycling batteries at www.northmontcorecycle.com). The radioactive material in ionizing smoke detectors is safely contained within the detector, but could be released if crushed in a landfill. Ionizing smoke detectors must be recycled for this reason, but they cannot be put into a household recycling bin. There are two options for properly recycling ionized or dual sensor smoke detectors:
Return to manufacturer: many companies will accept their brand of ionizing smoke detectors for recycling. The United States Postal Service provides a list of manufacturers that accept smoke detectors and their addresses. You must pay for postage and, in some cases, a small fee for recycling. Google provides a free shipping label to recycle their Google Nest smoke detectors.
Smoke detector recycling kit: Curie Environmental Services offers a smoke detector recycling kit to recycling ionizing smoke detectors, regardless of brand. The kits include proper shipping materials and paid postage. The kit will be shipped to your home and you can simply add your smoke detectors (battery removed) and drop off with the shipping carrier listed on the postage.
Smoke Detector Fact Sheet
There are two types of smoke detectors:
- Ionization detector uses a tiny amount of a radioactive isotope, Americium 241, between two electrically charged plates. A fire is detected when smoke passes between the plates, disrupting the flow of current and activating the alarm. You can tell if you have this type of detector if there is a radioactive symbol on the back of your detector.
- Photoelectric detector uses LEDs aimed away from a light sensor in the detector. When smoke enters the detector, it reflects the light onto the sensor, activating the alarm.
Dual smoke detectors are also available. The dual detectors have both ionization and photoelectric sensors. The ionization sensor is best for detecting flaming fires while the photoelectric sensor is best for detecting smoldering fires. It is recommended to have both detectors or a dual detector in your home.
Expiration:
- Smoke detectors must be replaced every 10 years.
- Smoke and carbon monoxide detectors must be replaced every 5 to 7 years.
- This is for both battery and hard-wired units as well as smart detectors, like google nest.
- The manufactured date can be found on the back of your detector.
Recycling of Smoke Detectors:
- Photoelectric smoke detectors may be disposed of in the trash.
- Montgomery County does not accept smoke detectors at household hazardous waste or electronics collections.
- Google will give you a free shipping label to recycle your google Nest detector.
https://support.google.com/store/answer/3036017?hl=en&ref_topic=3244667#zippy=
- Some manufacturers allow you to ship your expired ionization detectors back for proper recycling. Google is the only manufacturer to pay for postage. A list of companies accepting expired smoke detectors and the location to ship to can be found below and on the USPS website. Most companies will only accept their brand of detector.
| Manufacturer/ Distributer | Phone Number | Address for Return | Notes |
| American Sensors/Dicon Global | 800-387-4219 | Call to receive a number and return information | Accepts Dicon Global American Sensors brands only |
| Firex | 800-445-8299 | Firex c/o Disposal 28C Leigh Fisher Blvd. El Paso, TX 79906 | Website |
| First Alert/BRK | 800-323-9005 ext. 2 | Customer Service Dept 3920 Enterprise Ct Aurora, IL 60504 | Accepts up to four devices of First Alert/BRK brand at a time. Call ahead for mailing instructions |
| G.E. Security/ESL | 888-437-3287 | 12345 Southwest Levetan Dr. Tualatin, OR 97062 | Accepts G.E. Security/ ESL brands only |
| Honeywell | 800-328-5111 | Returned Goods Honeywell, Inc. Dock 4-MN10-3860 1985 Douglas Drive North Golden Valley, MN 55422 | Accepts Honeywell smoke detectors only |
| Kidde | 800-880-6788 Ext. 1 | 1016 Corporate Park Dr. Mebane, NC 27302 | Accepts Kidde brand smoke detectors only |
| Sears | Local Number | Some Sears locations are designated collection sites | Call to find out if local Sears will accept smoke detectors |
| System Sensors | 800-736-7672 Ext. 1 | Call to receive a reference number and return information | Will accept “System Sensor” brand only. Cost of $3.00 per sensor. |
| USI Electric/Universal | 800-390-4321 Ext. 1 | Attn: Disposal Dept. 7A Gwynns Mill Court Owings Mills, MD 21117 | Return only detectors that say “ionization” on the back. Accepts USI Electric or Universal Brand detectors only. Enclose a note that the smoke detector is being returned for recycling. |
https://about.usps.com/postal-bulletin/2012/pb22334/html/cover_025.htm
- Curie Environmental Services offers smoke detector recycling kits for ionizing smoke detectors of any brand. The kit includes proper shipping materials and postage and ranges from $70 for 4 to 5 detectors to $277 for 25 detectors. You can also send your smoke detectors without their kit at the cost of $11 per detector plus postage and packaging.