After putting in more than 70 hours researching fire safety, interviewing five experts, and reading well over a hundred pages of smoke-alarm data, we recommend the First Alert SA511CN2-3ST Interconnected Wireless Smoke Alarm with Voice Location as the primary alarm in a comprehensive whole-home fire-protection system.
Our pick
Available in a two-pack, these alarms can interconnect so that they all sound at once. They also tell you which room the fire is in.
The UL-certified First Alert SA511CN2-3ST alarm comes in a two-pack, and the units (and any additional ones) can interconnect so that if one sounds, they all sound, which can give you additional time to identify the problem and evacuate. This wireless-connection setup is internal to the alarms and does not require a phone app. You can also designate each unit by location so that if an alarm is tripped, all of them indicate which room the hazard is originating from. The First Alert SA511CN2-3ST is the only model that combines all of those features in one bundle—and at a price that’s just slightly above average for the category, it’s a good value. Also, because it has a voice alert rather than a beep or a tone, our interviewed experts told us, it’s more apt to wake a sleeping child.
Also great
Similar to our pick but also equipped with a carbon monoxide alarm, these photoelectric smoke alarms with voice alerts can interconnect and allow you to identify threats by location.
If you’re shopping for a smoke alarm and don’t already have carbon monoxide alarms installed, we recommend using the First Alert SCO501CN-3ST Combination Smoke and Carbon Monoxide Alarm with Voice Location on each floor. This photoelectric alarm is identical to our main pick save for an added carbon monoxide alarm, which detects CO from broken or improperly installed chimneys or fuel-burning appliances such as some furnaces, dryers, or water heaters. That feature adds notable cost, with a single unit typically priced a little less than the two-pack of our top pick.
Also great
The First Alert SA303CN3 is slightly better at detecting fast, flaming fires than the rest of our picks, but it’s generally slower to go off, and it’s best as a supplemental part of a system.
For the most complete and effective smoke alarm system, we also recommend adding one First Alert SA303CN3 Battery Powered Smoke Alarm per floor. This alarm employs a different detection technology, ionization, so it is slightly better at detecting fast flaming fires than our other picks. It’s not as good as a photoelectric alarm in detecting slow, smoky, smoldering fires—and in studies, ionization alarms have tended to sound a few critical minutes later—which is why we recommend it for supplemental use and not as your primary alarm system.
Also great
The PR710 can’t interconnect like our picks, but it does have a 10-year sealed battery, which some states and municipalities require.
The smoke alarms we recommend use AA or 9V batteries, but if your city or state requires a 10-year sealed battery in your smoke alarm, we like the First Alert PR710 Slim Photoelectric Smoke Alarm with 10-Year Battery. This UL-approved alarm has no connectivity, so it lacks the whole-house protection of our main picks, but otherwise it should offer the same smoke-sensing effectiveness. Research has shown (PDF) that 10-year batteries may not actually last 10 years, so we still recommend testing them on a schedule and not falling into complacency. First Alert also sells the P1210E 10-Year Battery Photoelectric Smoke Alarm, Slim Profile with Safety Path Light, which is the same alarm but with an added pathway light that turns on when the alarm is activated.
