Firefighters have flagged up their fears that a new computer system may be putting people’s lives at risk.
The Fire Brigades Union (FBU) said: “There have been numerous failures to actually mobilise fire appliances.”
East Sussex FBU secretary Mark Brown said: “We have seen repeated, catastrophic and potentially life-threatening failures of the service’s mobilisation system.
“Public and firefighter safety is being put at risk.”
But East Sussex Fire and Rescue Service said that it was sending crews to all emergencies and that the union’s criticisms included some inaccuracies.
The fire service said that it took seriously the safety of firefighters and the public and had “agreed to a joint investigation into all the IT matters” raised by the FBU.
The FBU said that it was raising concerns because the fire service was failing to send crews to emergencies including life-threatening incidents such as fires and water rescues.
It said: “The Fire Brigades Union (FBU) have been made aware that since the introduction of a new mobilisation system in East Sussex, there have been numerous failures to actually mobilise fire appliances.
“Last week the FBU met with Chief Fire Officer Dawn Whittaker and the senior leadership team to demand an immediate joint service/FBU investigation into the failures due to the fact the service have failed to investigate.”
East Sussex FBU brigade chair Simon Herbert, who serves at Hove, said: “Not only have we seen the service fail to mobilise appliances to emergencies, the same failing system has also resulted in up to date risk critical information not being available to firefighters.”
East Sussex FBU brigade secretary Mark Brown said: “Since the system went live in March, we have seen repeated, catastrophic and potentially life-threatening failures of the service’s mobilisation system.
“Public and firefighter safety is being put at risk due to these failures.
“Not only has the primary system failed, we have also seen failures of the back-up systems.
“The situation with the new mobilisation is totally unacceptable. The system has proved to be totally unfit for purpose.”
The fire service said: “East Sussex Fire and Rescue Service crews are being sent to all emergencies reported by members of the public on 999.
“We went live with a new ‘4i’ system in our joint Sussex Control Room on (Tuesday) 20 March this year and we would seek to assure both the press and the public that in terms of mobilising and the software system it is performing well.
“We have a system to monitor and manage all parts of the mobilising process.
“We are actively investigating and are resolving a small number of issues relating to the IT equipment on fire stations and fire engines. These are additional systems.
“When any equipment defects arise, the service implements its back up procedures to ensure crews and officers are mobilised – and that the defects are dealt with.
“At a meeting on Monday 14 May, it was agreed with the Fire Brigades Union that we would ensure a joint investigation into all the IT matters. Initial facts and data have been gathered as part of this process.
“We are also ensuring that our colleagues in West Sussex Fire and Rescue Service and East Sussex Fire Authority are fully aware of the situation.
“We are disappointed that there are a number of inaccuracies in the notice made by the Fire Brigades Union.
“Historically there have been some acknowledged issues with IT at the service and there is a clear multimillion-pound plan for improvement which is being delivered.
“The control room and mobilising systems are part of that future and ongoing investment and we are actively seeking ways to improve the resilience of our service.
“We will always take the safety of the public and our fire crews very seriously and we remain confident that we can respond to the needs of our community quickly and effectively.”