Do Fire Alarms Work in a Power Cut?

Fire alarms are one of the first types of fire safety equipment your business will employ. In the event of a fire, they are an easy and reliable way to detect danger and alert those within the vicinity. But with the recent news of possible temporary power outages, nationwide ‘blackouts’, or at least a strain on energy this winter, is your fire alarm at risk of malfunction as we head into the colder months?

Below, we outline the scenarios you may experience and what to do when it comes to taking care of your fire alarms.

The tips below do apply to both your domestic and commercial fire alarms, here at Target Fire Protection we specialise in installing commercial fire alarms and provide servicing and maintenance.

Do fire alarms still work during a power outage?

If your premises is operating a battery-powered alarm system, a power outage is unlikely to affect your alarms. However, most businesses will have at least one fire alarm ‘hardwired’ to the mains.

The extent to which your alarm operates in an outage depends on its health in the first place. If you keep up with a maintenance schedule, the fire alarms and their backup batteries should have been checked and approved upon their last inspection. You can therefore expect they would be operational in the event of a power outage, as the backup batteries would activate.

Types of fire alarm backup batteries

Many fire alarm systems that are mains powered have two backup batteries to call upon in a blackout. The first is a backup battery in each external sounder – the type of alarm we often see ourselves on the ceiling. And the second is the main, large lead battery that resides in the control box of your alarm system. This lead battery is designed as the failover for your whole system, to replace the mains power should it go out.

During an outage, at least one of these failover systems should work. And in more advanced alarm systems, backup batteries are able to recharge automatically when the mains power is present.

However, backup batteries stop fully replenishing after so many charges and need replacing every 3-5 years (or sooner if you have had several power cuts). Though an outage itself does not damage your alarms, the batteries may need replacing sooner than usual if several outages occur in a short period of time – a possible scenario in the current energy climate. Sticking to a maintenance schedule is crucial.

Why is my alarm sounding after an outage?

When a fire alarm rings during a power cut, it almost always means a battery is dead. Whether it’s your kitchen fire alarm or at work, ringing smoke alarms should be checked for faulty batteries, with engineers called in to inspect where appropriate.

As we briefly explained above for mains powered setups, in the fire alarm control box is a backup battery for the whole system in case of mains failure. There are also backup batteries in each external alarm sounder to protect against mains failure. If the external sounders ring during a power cut, this alerts to a faulty or dead lead battery in the main control box.

Conversely, if there is only a dull tone or beep when you access the main control box, this would indicate the lead battery was successful in backing up your system. If there are no sounds coming from either, you may need to speak to a professional.

Does a commercial fire alarm have to be connected to mains power?

There is currently no law requirement for any commercial property to have a fire alarm system. However, the FSO does state that adequate fire safety equipment be used and this most often takes the shape of a fire alarm system. Furthermore, due to the unpredictability of a pure battery-ran fire alarm setup, at least one of your alarms is often linked to the mains power. In short, mains power fire alarms aren’t a legal requirement, but they are a must for many safety-conscious business owners.

Do I need to reset my fire alarm after an outage?

After you’ve dismissed alerts and checked the backup batteries are working, your alarms should return to normal operation. Depending on your system, uncharged or faulty batteries can be replaced by yourself.

If your alarm doesn’t work after an outage, a reset may be needed. This can be as simple as entering a system code or fixing a blown fuse. In more complex cases, an engineer may be needed.

Ensuring your fire alarm is ready for a power outage

The last thing anyone needs after a power outage is a faulty fire alarm system. To ensure your alarms are fit and ready for the potential energy turmoil this winter could bring, a regular maintenance schedule is well worth the investment.

At Target Fire Protection, we have vast experience in helping businesses across Rochdale, Manchester and the North West keep their fire alarms in working order. If you’re concerned about the potential impacts of a power outage this winter, please get in touch with our friendly team to arrange a maintenance visit.