The fire service is being “crippled” by cuts in the number of control room staff, a report claims.
The Fire Brigades Union (FBU) said more than 500 posts had been axed across the UK since 2010 - a quarter of the total.
The loss of so many jobs had led to “chronic” shortages, with staff having to work overtime, said the union.
More fire services are introducing 12-hour shifts, which is disruptive to family life, especially as most control room operators are women, the FBU said in a report.
Lynda Rowan O’Neill, of the FBU, said: “Control staff have been subjected to more than a decade of failed government policy, characterised by cuts, mergers and underinvestment.”
Concerns have also been raised about the reduction in control room staff in Greater Manchester.
Gary Keary, secretary of the FBU in Greater Manchester, said: “It’s probably worth mentioning that the four fire and rescue services - Greater Manchester, Lancashire, Cheshire and Cumbria - who now make up North West Fire Control had 160 control staff when they had their own individual control rooms, and now there are only 59 - almost a loss of two-thirds.
“Greater Manchester alone used to have a minimum of eight control staff on duty. North West Fire Control have eight in the morning and more frighteningly seven overnight - for all four brigades - and that figure includes the supervisors.
“This used to be a job for life but transferees and new starters are both leaving.
“Both sickness and stress levels are high.”