It’s often the last thing that comes to mind for panicked residents in bushfire prone areas, but it can be the difference between life and death.

Mobile phone coverage.

True, you may receive advice from your local fire authority about finding an open space away from trees because they can block your phone signal.

But you’re often not told how a bushfire can actually degrade your signal, meaning you may miss important alerts and be unable to make or receive calls.

Sadly, there are regional and remote areas that still have no mobile phone reception.

Residents watch anxiously as the fire front approaches a property in Colo Heights, NSW. Photo: Getty

Take, for example, the small town of Mount Seaview in NSW.

On Friday, an out-of-control fire consuming more than 67,700 hectares tore through the area which is a mobile blackspot, meaning the residents there are virtually unreachable.

“They’re in a very dire situation,” said Dr Stanley Shanapinda, a researcher in Computer Science and Information Technology at La Trobe University.

“There is no way they can call for help or be informed about how at-risk they are and how to prepare themselves,” he said.

Phone coverage is made possible by a phone tower which gives a signal that is measured by the bars on your phone.

A phone tower is your antenna which uses radio waves to communicate with your phone. Photo: Getty

If you’re reliant on a tower that is in an area where there is a bushfire burning, or if a piece of communications equipment, such as relay tower, is in the path of that fire, you run the risk of completely losing access to a phone service if it is damaged or happens to burn down, Dr Shanapinda said.

Even if the tower remains intact, the heat from the fire can create “plasma” which then interferes with the “magnetic field” and weakens the phone signal, he said.

In an emergency, the mobile network in rural and regional areas can also become congested to the point where incoming calls are blocked, new connections can’t be formed, and not all texts or alerts get delivered.

“It’s like everyone trying to get through the door at the same time but the door is only so big,” Dr Shanapinda said.

When this happens, turn your phone off and back on again as the signal may become stronger because someone else has dropped off, he said.

Buying a signal booster gives you the best chance at keeping a strong phone signal, he added.

Also remember to use your phone as little as possible because it will exhaust the battery. So carry a second battery or portable charger and, just to be sure, invest in a charging cord for your car.

A state of emergency was declared by NSW Premier Gladys Berejiklian on Monday 11 November and is still in effect. Photo: Getty

“People just think ‘oh the power can go off and then the fridge may be going off’,” Dr Shanapinda said.

“But they don’t know that if the power goes off, I’m not going to be able to charge my cell phone.”

Fire authorities responsible for giving bushfire preparation checklists should tell residents where to find their nearest phone tower, provide alerts when they are down and inform people when not to expect a phone connection, Dr Shanapinda said.

He said it’s simply not enough to prepare safety bunkers, fire blankets, extinguishers and the like in a fire emergency.

A weak phone signal can present as a “real threat to your life”, he said.