Smoke alarm
Warns of smoke from fire.
Smoke-only models do not detect CO.HOUSEHOLD SAFETY · CHOOSE & CHECK
Early warning. A clear way out.
Check the alarms and escape plan you already have. Then choose equipment that fills a real gap and works with your home.
Three jobs. Different equipment.
Carbon monoxide alarm
Warns of a gas you cannot see or smell.
CO-only models do not detect smoke.Fire extinguisher
A limited tool for a trained user.
Never delay escape to use one.A combination smoke/CO alarm performs two detection jobs. “Dual sensor” can instead mean two smoke sensors. Read the exact label.
Walk through your home
Bedrooms: smoke alarms in every bedroom.
Outside sleeping areas: smoke and CO coverage.
Every level: smoke and CO coverage, including the basement.
General guidance, not a placement drawing. Follow each manual’s mounting locations and clearances, plus local requirements. Sources: USFA smoke alarms and USFA CO alarms.
Match the system before the shopping cart.
| Your situation | What to check | Next action |
|---|---|---|
| Replacing a wired alarm | Exact model, power supply and interconnect compatibility | Have a qualified electrician identify the replacement |
| Adding standalone coverage | Whether local rules require hardwiring or interconnected alarms | Confirm the permitted type before choosing a battery model |
| Someone may not hear an alarm | Alerting needs while asleep, including hearing loss | Ask about compatible strobes, bed shakers and other listed alerting devices |
| Buying an extinguisher | Fire classification, recognized listing, operating weight and mounting location | Get training and choose a unit you can safely handle |
USFA recommends interconnected smoke alarms and coverage using both ionization and photoelectric sensing, or dual-sensor smoke alarms. The examples below cover different replacement and standalone situations; no single example is a complete alarm plan.
Renting? Report missing, expired or faulty equipment to your landlord or building manager. Confirm the approved replacement rather than removing required equipment. Your fire department’s nonemergency line may offer installation guidance or alarm assistance.
Four specific examples to check against your needs.
(opens in a new tab)Hardwired smoke-alarm replacement
First Alert SMI100-AC (opens in a new tab)
A candidate when a qualified installer confirms it fits your existing system and local requirements.
Features: Ionization smoke sensor; hardwired power; replaceable 9V backup battery; compatible wired interconnection.
Check first: Smoke only: no CO detection. Do not mix alarm brands or models on an interconnect circuit without documented compatibility. This single ionization model does not by itself provide both smoke-sensing technologies.
Manufacturer information checked 2026-09-10. Research-based example; not hands-on tested.
(opens in a new tab)Standalone carbon monoxide warning
First Alert CO710 (opens in a new tab)
A CO-only option where a standalone battery alarm meets the household’s requirements.
Features: Electrochemical CO sensor; sealed 10-year battery; digital display; end-of-life warning. Manufacturer lists UL 2034.
Check first: CO only; does not detect smoke or interconnect. Its manual calls for testing weekly, after installation and after cleaning. Replace at end of life or after 10 years, whichever comes first.
Manufacturer information checked 2026-09-10. Research-based example; not hands-on tested.
(opens in a new tab)Multipurpose household fire extinguisher
First Alert HOME2PRO (opens in a new tab)
A candidate for a trained adult who can comfortably operate it, with an accessible mounting location.
Features: 2-A:10-B:C rating; metal head; pressure gauge; wall hook; rechargeable by a certified professional after use.
Check first: Not a substitute for escaping. Match HOME2PRO and the 2-A:10-B:C label: the manufacturer page also contains a different 1-A variant. Do not assume a household ABC unit suits every fire or commercial cooking hazard.
Manufacturer information checked 2026-09-10. Research-based example; not hands-on tested.
Standalone photoelectric smoke alarm
Kidde DETECT 20SD10 (opens in a new tab)
A photoelectric option where a standalone battery alarm is permitted; confirm placement and the whole-home detection plan.
Features: Photoelectric smoke sensor; sealed battery; no wired or wireless interconnection. Manufacturer data sheet lists weekly button testing.
Check first: Smoke only, not CO. Not a replacement for required hardwired or interconnected coverage. Single photoelectric sensing is not dual-sensor coverage. Follow the manual for replacement; a 10-year warranty is not a battery-performance guarantee.
Manufacturer information checked 2026-09-10. Research-based example; not hands-on tested.
Amazon buttons are affiliate links. Manufacturer links support the specifications. As an Amazon Associate I earn from qualifying purchases. These examples are not a ranking or a claim that one brand is best.
If it sounds, act on the warning.
Fire or a CO emergency alarm
Get everyone outside to safety and call 911 from outside. Stay out until emergency responders say it is safe. Do not search for the source of CO.
If you suspect CO exposure, seek immediate medical help. A normal-looking display does not overrule symptoms or an emergency warning. CO710 manual: alarm response and testing (PDF) (opens in a new tab).
Learn the difference between your model’s emergency signal, low-battery chirp and end-of-life warning from its manual. Never remove batteries to silence an unexplained alarm.
An extinguisher is an option only when every condition is met
- Others have been alerted and the fire department called.
- You are trained and physically able to operate it.
- The fire is small and contained; you are safe from toxic smoke.
- You have a clear escape route and the correct extinguisher.
If any condition is missing or uncertain, leave. Arrange practical training through your local fire department before an emergency. USFA extinguisher guidance.
Keep outdoor stoves and generators outdoors. An alarm does not make unsafe equipment use safe. CDC CO prevention.
Match the escape plan to the people and building.
Someone may not hear the alarm
Ask your fire department and a qualified installer about listed alerting equipment that works with your alarm system and supports waking the person while asleep. A louder alarm alone may not resolve the need.
USFA identifies vibrating pads and flashing or strobe lights as options. Choose the combination for the person and setting.
USFA accessible fire-safety guidanceAn upstairs room needs another way out
Discuss the room and occupants with your fire department before choosing a portable escape ladder. Check window dimensions, height, clear landing space and who can use it. A ladder does not replace a building escape plan.
Version trap: Kidde labels its KL-2S a single-use design. Follow its instructions; do not assume an emergency ladder can be deployed for practice and repacked for later use.
Kidde KL-2S specifications and instructions (opens in a new tab)Make it a household routine.
Test
Test smoke alarms at least monthly, or more often when the manual requires it. The Kidde 20SD10 data sheet calls for a weekly button test. Follow the CO alarm’s testing schedule and instructions. Check that the extinguisher is accessible, undamaged and shows the correct pressure.
Check dates
Replace smoke alarms at 10 years from manufacture, or sooner if required. Follow CO replacement instructions. A warranty is not a service-life guarantee.
Practice leaving
Identify two ways out of each room where possible, keep exits clear, choose an outside meeting place and agree who helps children or anyone needing assistance.
Discuss your building’s fire procedure if you live in an apartment. Practice together. USFA escape planning.
Reviewed September 10, 2026 against the primary sources linked here. General household guidance; your fire marshal, building requirements and product manuals determine the installation. How we research recommendations.
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