Emergency Sound Safety Check

Most smoke alarms beep at around 3,100 Hz — one of the first frequencies to fade with age-related hearing loss. Even mild high-frequency hearing loss can make these alarms inaudible, especially while sleeping. Low-frequency alarms (520 Hz) and strobe or bed-shaker systems are much more effective for people with hearing loss.

Prioritise by what actually wakes people. A 520 Hz low-frequency alarm performs best (92% woken in sleep testing), a bed shaker is a strong second (80-84%), and a strobe is the weakest at 27% — useful as a supplement, not as your main protection. On products: Gentex's PLACE is the main residential 520 Hz smoke and CO alarm; Lifetone makes a bedside unit that listens for your existing smoke alarm and responds with a 520 Hz tone, a spoken alert and a bed shaker — though note it does not cover carbon monoxide, so you would still need an accessible CO alert. Kidde's strobe for the hearing impaired has been discontinued, and it was an accessory requiring an interconnected alarm rather than a detector in its own right. Some fire departments run free installation programmes for qualifying residents, often including deaf and hard of hearing households — worth asking your local station, though they rarely stock specialised equipment like bed shakers.

Yes — a vibrating pad goes under your pillow or mattress and is triggered by your smoke detector. They perform well: in controlled testing of adults with 25-70 dB hearing loss woken from deep sleep, bed and pillow shakers woke 80-84% of people as sold. That said, they are not quite the best option — a 520 Hz low-frequency alarm woke 92% in the same study. The ideal setup for most people is a 520 Hz alarm plus a shaker, particularly if you sleep without hearing aids. If you can only have one, the evidence favours 520 Hz.

Yes, but with one important limit. Smart alarms such as the First Alert SC5 send push notifications when they detect smoke or CO (Google discontinued the Nest Protect; the hardware is rated for 10 years from manufacture, and First Alert makes the replacement). Dedicated alarm-listener sensors can hear a standard alarm sounding and alert your phone. Your phone's own accessibility features can also listen for alarms — Sound Recognition on iPhone, Sound Notifications on Android — but Apple states plainly: "Don't rely on your iPhone to recognize sounds in circumstances where you may be harmed or injured, in high-risk or emergency situations." Google publishes no comparable guidance either way, and its own setup instructions tell you to leave the phone unobstructed in the middle of the room. Use these as a helpful extra layer. Do not use them as your smoke alarm.

Conventional alarms sound at typically about 3,100 Hz, in the three-beep temporal pattern that has signalled fire since 1996. A 520 Hz square wave is dramatically better at waking people with hearing loss — 92% versus 56% for the high-pitched alarm in controlled sleep testing. On the codes, the detail matters: NFPA 72 requires 520 Hz where alarms are meant to wake sleeping occupants who have mild to severe hearing loss, while it is NFPA 101 that requires it in new hotels, dormitories and apartment buildings. For an existing private home, no code requires one — it is strongly recommended rather than mandated. And availability is thinner than you would hope: the Gentex PLACE is currently the main residential smoke and CO alarm with a built-in 520 Hz sounder, so this is a deliberate purchase rather than something you will find on a supermarket shelf.

Extremely dangerous. Carbon monoxide is colorless and odorless — your detector is your only line of defense. If you can't hear it, you need a CO detector with a strobe light or one connected to a smart home system that sends phone alerts. This is not something to delay on.

Yes, and it's free. On iPhone, go to Settings > Accessibility > Sound Recognition — your phone can listen for fire and smoke alarms, sirens, doorbells, and more than a dozen other sounds, then flash a notification when it hears one. Apple builds this feature for deaf and hard of hearing users, and a HomePod can also listen for smoke and CO alarms and send an alert to your iPhone. On Android, turn on Sound Notifications in Settings > Accessibility for similar alerts. These are excellent backups, but don't rely on a phone alone while you sleep — pair it with a strobe or bed shaker.

Yes, especially for sleeping. Hearing aids come out at bedtime, which is exactly when a missed smoke alarm is most dangerous. Even if you hear alarms fine during the day, you need a bed shaker, strobe, or low-frequency alarm covering the hours your aids are on the nightstand. Think of hearing aids as your daytime coverage and alerting devices as your nighttime coverage — you need both.