Most people's entire communication plan is a mobile phone, and a mobile phone depends on a mast, a backhaul connection, mains electricity at several points in the chain, and a network that is not overloaded. In any widespread event, at least one of those fails.
Some of what follows is free and takes two minutes, and almost nobody has done it.
Text beats call, nearly always
SMS succeeds where a voice call fails. A call needs a continuous two-way connection held open for its whole duration. A text is a tiny burst that needs a sliver of signal for a moment.
A queued text sends itself. Compose it, hit send, and if there is no signal the phone holds it and delivers it the instant one appears, including while it is in your pocket and you are walking. You do not have to be watching.
Texts also get through congestion. In a major incident the voice network saturates within minutes as everybody rings everybody. SMS uses a different, much lighter path and often keeps working when calls will not connect.
So the habit is: send a short text first, then try to call. Not the other way round.
Keep it short and factual: who you are, where you are, whether you are safe, and what you intend to do. "Safe, at Mum's, staying tonight, phone on 20%" is worth more than three calls that do not connect.
999 is different
Emergency SMS, which needs setting up first
You can text 999, and it is the route that works when there is not enough signal for a call, as well as being the standard service for deaf and speech-impaired users.
It only works from a registered phone. Registration is free and takes a minute:
- Text the word register to 999.
- You get a reply with instructions.
- Follow it, and you get a confirmation.
This cannot be done at the moment you need it. An unregistered phone texting 999 in an emergency does not reach the emergency services.
Do it for every phone in the household today. Including the children's, including the spare, including the old one in the drawer. There is no cost and no downside.
What actually stays up in a power cut
The picture has changed considerably in recent years and most households are working from an out-of-date mental model.
The critical change: the UK is moving telephone services off the old copper network onto digital voice delivered over broadband. A digital voice line stops working the moment your electricity does, because the equipment is in your house rather than at the exchange.
Two practical consequences:
- Keep one corded analogue phone if you still have a line that supports it. A cordless handset is useless in a power cut even on a line that is still live.
- If you have digital voice, find out whether your provider supplied a battery backup unit. They are obliged to offer one to customers who depend on the line, and most people who have one have never tested it or have unplugged it.
Mobile masts have batteries measured in hours, not days. Expect mobile coverage to thin out and then go as an extended outage continues, starting with the smaller cells.
Making the battery last
The phone is your comms, your torch, your map and your camera, and it is a few hours of use.
- Aeroplane mode is the biggest single saving. A phone with no signal transmits at full power constantly hunting for one, which flattens it far faster than normal use.
- Agree check-in times and turn the radio on only for those. Ten minutes on the hour beats being reachable and dead by lunchtime.
- Screen brightness down, and use it as little as possible. The screen is the second largest drain.
- Keep it warm. Cold reduces available battery capacity dramatically. Inside a jacket, next to your body, not in an outside pocket.
- A power bank, charged, is the single best thing to own. Charge it monthly whether or not you have used it.
- Wind-up and solar chargers work and are slow. A wind-up radio with a USB output charges a phone enough for a text, which may be all you need.
- Download offline maps and install a positioning app now, so the phone is useful without any network at all.
Finding signal
- Height. Upstairs, a hill, a window, a doorway. Even a few metres matters.
- Outside, and away from thick walls. Stone, foil-backed insulation and modern coated glazing all block signal significantly.
- Face away from the hill, not into it.
- Stand still once you have a bar. Walking while a text sends can drop it.
- Try again at a different time. Congestion eases, and networks are restored progressively.
When there is no network at all
- PMR446 handhelds for local contact within a few hundred metres to a few kilometres. See radio.
- A physical note. Left at the house, at the meeting point, in a known place. Say who, when, where you have gone and when you expect to be back, and put the time on it. This is the oldest system and it works with no infrastructure at all.
- A person. Somebody walking a message is slow, reliable and, in a genuine failure, was the method for most of human history.
- Pre-agreed defaults, which are the real answer: if nobody can reach anybody, everybody already knows what happens. See meeting points and a household plan.
The plan that needs no communication is the plan that survives no communication.
The out-of-area contact
The technique that costs nothing and works surprisingly often.
In a local event, local networks congest first. Calls within the affected area fail while calls out of it get through, because the load is concentrated where the event is.
So nominate one person well outside your area as the household's message relay. Everybody in the household knows their number by heart, or carries it written down. Everybody rings or texts them, and they hold the picture of who is where.
- Choose somebody geographically distant, a relative or friend in another part of the country.
- Ask them first, and tell them what the role means.
- Everybody has the number on paper, not only in a phone that may be dead or lost.
- Children should have it too, learned or written on a card in a school bag.