Response times to emergencies in some areas of the Westcountry could rise during today's strike by firefighters, service bosses have admitted.
The Fire Brigades Union (FBU) is staging a four-hour stoppage today in its long-running dispute with the Government over pensions reform.
Contingency plans have been put in place by both Cornwall Fire and Rescue Service and Devon and Somerset Fire and Rescue Service "to ensure the public will receive a response to all 999 calls during periods of industrial action".
The Devon and Somerset service said it expected the majority of fire stations "to be operating as usual during the strike" which runs from noon until 4pm.
But it admitted that "some locations within the two counties will be affected". A pool of non-union firefighters are being used to respond to emergencies in those areas although the service said "response times could be extended as a result".
Chief Fire Officer Lee Howell said: "The majority of our stations will be available and the public will get a response to an emergency wherever they are in Devon and Somerset.
"Although there will always be a response, due to the likelihood of a reduced service, we will be prioritising calls to emergencies where there is a risk to life. Periods of industrial action are always difficult for everyone involved and the public can help us at this time by taking extra care."
Cornwall's Chief Fire Officer Des Tidbury said it had "robust contingency plans in place to maintain minimum levels of cover".
He added: "We will continue to respond to emergency calls and will obviously prioritise those where lives are at risk. Public and firefighter safety remains of paramount importance and we will give the best service to the people of Cornwall within the limitations of the resources available to us.
"I would urge everyone to take extra care and time to think about fire safety in their home during this period, check smoke alarms, ensure you know what you would do if there was a fire and not making unnecessary calls to the fire and rescue service."
The FBU announced last week it would be taking industrial action after almost 80% of its members voted in favour of striking.
Matt Wrack, Fire Brigades Union General Secretary, said: "This initial strike is a warning shot to government. Firefighters could not be more serious about protecting public safety and ensuring fair pensions. Governments in Westminster and Cardiff have simply refused to see sense on these issues.
"It is ludicrous to expect firefighters to fight fires and rescue families when in their late-50s – the lives of the general public and firefighters themselves will be endangered. None of us want a strike, but we cannot compromise on public and firefighter safety."