False fire alarms, caused by either cooking fumes or faulty electronics, are some of the main causes behind 23.9% (2,502) of the 10,466 incidents Lincolnshire Fire and Rescue attended last year.
Firefighters however, saw a decrease of 2,660 call-outs compared to the previous year.
A report before a county council scrutiny committee next Tuesday says the reduction is mainly due to attending fewer medical emergencies, however, this still forms the biggest chunk of call-outs for the service.
More than a fifth (474) of fires Lincolnshire Fire and Rescue attended across the county last year were started deliberately.
Five people died in fires last year, while the service also had to recover six bodies from the water or from situations involving suicide.
Firefighters helped 266 people involved in car crashes, 117 stuck in lifts and 64 people physically trapped.
Last year’s hot weather also saw an increase in fire-related incidents during the summer including farm vehicles, field, grassland and forest fires.
Only 37 callers had a malicious intent to divert resources or cause trouble.
The report before councillors says: “False alarms are a significant drain on our resource, not just financially but by having fire engines being dispatched to deal with the call, and as such not available to attend real 999 calls.”
A spokesman for the service said there were a range of causes for automatic alarms going off but the main ones were cooking fumes or faulty electronics.
Sean Taylor, Area Manager at Lincolnshire Fire and Rescue said: “Whenever we carry out inspections at high risk premises, where automatic alarms are fitted, we offer support and advice in maintaining equipment and preventing them being activated unnecessarily.
“Where businesses don’t make improvements and have repeated call-outs, we can issue a charge for unnecessary incidents.
“In housing with automatic alarms, we’d always recommend that people don’t leave their cooking unattended to prevent sparks, steam and fumes activating alarms accidentally.”
Figures show that of 2,024 fires the service attended in 18/19, 474 were classed “deliberate”.
Of those, 218 were more serious fires that harmed people or property, while 256 were smaller fires not involving either – for example bin fires and derelict buildings or vehicles.
However, the largest number of incidents the service attended were of a medical nature with staff called to 4,360 co-responder incidents – a partnership with EMAS and LIVES which sees the service called on to attend medical issues.
This sees the service carry out non-invasive treatment, including the use of defibrillators and using its own three ambulances to transport patients to hospital.
This figure is down from 7,825 the previous year – something officers put down to a change in EMAS protocols and fire service “staffing issues”.