Buying guide
How to choose a personal alarm you will actually carry.
Personal alarms all look similar and all claim to be loud. The differences that matter show up later: on the fourth month, in the rain, at the moment you need one hand for the door and one for the alarm.
Start with the attachment, not the alarm
The best alarm in the world does nothing from inside a drawer. Whether you carry it every day is decided by how it attaches, and that question is worth answering first.
A keyring works because your keys already come with you. A clip that needs a specific bag works only on the days you take that bag. If carrying it requires a decision each morning, some mornings will go the other way.
Where to carry your alarm so you can reach it fast
Where your hand finds it without looking. The simplest place is your keyring: your keys are already in your hand when you get home, and the alarm comes with them.
On a bag, it goes on the outside, clipped to a strap or a ring, on the side of the hand that holds nothing. At the bottom of the bag, under everything else, it takes longer to reach. OYA weighs 65 g and clips on with its gold clip, supplied in the box.
Rehearse the movement at home, without looking and without pulling: your hand goes down and finds the loop. If it has to search, move the alarm.
- Keyring: in your hand when you get home
- Outside of the bag: within reach, on the side of your free hand
- Bottom of the bag or a closed pocket: slower to reach
Keyring alarm, alarm bracelet or SOS button: which format
Three types of personal alarm share the shelf. They do not answer the same question, and that tells them apart long before the spec sheet does.
A keyring alarm makes noise, straight away. It comes with you because your keys already do, and it sits in your hand for the length of a walk.
An alarm bracelet is worn on the wrist: nothing to look for, nothing to dig out of a bag. In return, you have to put it on every morning, like a watch, and charge it like one. Before buying, look at how it is triggered, and at what stops it going off by itself under a sleeve.
A portable SOS button is not trying to make noise: it alerts someone. It is often the right choice for a person who lives alone or worries about a fall. Two questions to ask before buying: does it need a subscription, and what does it do where there is no signal?
So the choice comes down to what you expect: being heard by the people around you, or having someone further away alerted. Some devices do both, which is the whole question of what happens after the noise, further down.
- Keyring alarm: noise straight away, always on your keys
- Alarm bracelet: on the wrist at all times, provided you wear it every day
- Portable SOS button: alerts someone close to you, without trying to make noise
Read the decibel figure with some suspicion
Decibels are measured at a distance, and the distance is rarely printed next to the number. The same siren can be sold as 120 dB or 140 dB depending on where the microphone sat.
Anything from about 120 dB upwards is genuinely hard to ignore at close range. Past that, the pitch matters more than the number: a high, uneven tone cuts through traffic far better than a low steady one.
Ask what happens after the noise
A siren does one job: it makes people look. It cannot call anyone, and it cannot say where you are. In an empty street it is a very loud way of being alone.
This is the real dividing line in the category. Some alarms only make noise. Others also trigger a phone SOS call and send a position message to people you chose, so the noise reaches someone who can act on it.
You will often be offered two devices for this: an alarm that makes noise, and a connected button that alerts your people. That is two purchases, two places on the keyring, and two things to recharge. So the real question is whether one device does both. OYA does: the same pull on the loop sets off the siren, and if a phone is paired over Bluetooth, its native SOS calls the emergency number and sends a message with your position to the contacts you chose. There is no app to install, because that SOS is already in the phone.
- Noise only: good in a busy street, useless in an empty one
- Noise plus alert: someone knows, but not where you are
- Noise plus phone SOS plus position message: someone knows and can come
Check how it is powered and how it is triggered
Once flat, an alarm does nothing, whether it runs on batteries or on a rechargeable cell: the device looks the same, and you find out at the worst possible moment. So check how its charge level can be read, and pick a charging rhythm you will keep to. OYA has no battery light or beep: it charges in about 1 h, roughly every six months, and on Android its level shows in the phone’s Bluetooth settings.
The trigger matters just as much. A loop you pull with one hand works in the dark, with gloves, without looking. A small button you have to find and hold does not, and a device that goes off in your pocket twice a week will be left at home by the third week.
Most alarms on the market use a pull pin: a separate part you rip out, which then stays in your hand or drops on the ground. It is proven, with one catch you only find out in use: to silence the device, you have to find the pin and put it back. In the dark, on a pavement, that is not always possible.
A sliding loop does the same gesture with no separate part. It stays attached to the device: you pull it up to trigger, you push it back down to stop. Nothing to refit, nothing to lose, and stopping is as simple as starting. That is the mechanism OYA uses. No mechanism, this one included, guarantees that something in a bag will never pull on it: the most that can be said is that ordinary jostling is not enough.
- Pull pin: proven, but you have to find it again to stop the noise
- Sliding loop: stays attached, push it back down to stop
- Button: the most discreet, and the hardest to find in the dark
The criteria, one by one
Buying guides compare alarms on the same criteria. Here they are in order, with what to read on the product page, and OYA’s answer to each, including when it is no.
| Criterion | What to check | On OYA |
|---|---|---|
| Trigger | A one-handed move, without looking, and how the siren stops | A loop you pull with one hand; it stays attached, so there is no pull pin to lose |
| Measured decibels | The figure AND the distance it was measured at; without it, two figures cannot be compared | 130 dB measured at 30 cm |
| Continuous siren | It keeps sounding until you stop it, and how you stop it | Around 90 minutes non-stop on a charge; push the loop back down to stop it |
| LED light | A light you can use without setting off the siren | A white LED, steady or flashing, switched on by the side button alone |
| USB-C charging | Batteries or rechargeable, and the stated battery life | Rechargeable over USB-C, around six months between charges |
| Without a phone | Does the siren go off from the device alone? | Yes: the siren and the light work with no phone and no network |
| Alerting people close to you | Does it tell anyone, and how? | Paired over Bluetooth, it triggers the phone’s built-in SOS, which calls emergency services and sends your location to the contacts you chose |
| Rain resistance | A stated protection rating | OYA is not waterproof |
| App and subscription | What you have to install or pay for each month | No app, no account, no subscription |
What a personal alarm does, and what it does not
It does one thing: a very loud noise that draws attention around you. It stops nobody and does not guarantee that anyone steps in.
- What it does: a very loud noise, at once, with one move
- What it does, paired with a phone: set off that phone’s SOS
- What it does not: stop anyone, or guarantee that someone steps in
- What it does not: call emergency services itself; the paired phone makes the call, if it has signal
Any questions?
Keyring alarm, alarm bracelet or SOS button: which one should you choose?
It depends on what you expect. A keyring alarm makes noise so that the people around you hear you. A portable SOS button alerts someone close to you, usually silently. An alarm bracelet stays on the wrist, provided you wear it every day. Some devices do both the noise and the alert.
Pull pin or sliding loop: what is the difference?
A pull pin is a separate part you rip out: proven, but you have to find it and put it back to stop the noise. A sliding loop stays attached to the device and pushes back down to stop it, with nothing to refit and nothing to lose. Both trigger just as well; the difference shows up at the moment you want it to stop.
How many decibels should a personal alarm have?
Around 120 dB and above is loud enough to be impossible to ignore at close range. Beyond that figure, the pitch and how far it carries matter more than the number on the box.
Are personal alarms legal to carry?
In the European Union, a personal alarm is an ordinary noise making device and is legal to carry and to give as a gift. Unlike sprays or blades, no permit or age rule applies.
Is a safety app enough on its own?
An app can call for help and share your location, but only if you can unlock your phone and find it. A device on your keys removes the unlocking, the finding and the aiming.
Do personal alarms need a subscription?
Not all of them. An alarm that only makes noise needs nothing, while a monitored alarm comes with a monthly subscription, and for a portable SOS button it is the first question to ask before buying. OYA needs none: its alert goes through the SOS already built into your paired phone.
