Data released by the Fire Authority shows there are areas of the county that cannot be reached within the 10 minutes target.

Hertfordshire Fire and Rescue Service currently operates a network of 29 fire stations around the county – some of which are ‘wholetime’, some ‘on call’ and some of which are not crewed at night.

And they aim to get a fire engine to a house or building fire within 10 minutes, on 90 per cent of occasions.

But a map – included as part of the draft Integrated Risk Management Plan – shows not all areas can be reached within 10 minutes.

Areas marked in blue – predominantly focussed on the more populated, urban areas – can be reached in 10 minutes, it suggests.

Those areas marked in pink can be reached in 13 minutes. Those marked green in 16.

The data is included in the draft Integrated Risk Management Plan, which sets out the future vision and priorities for the Fire Service.

It also includes data on how often the targets were met across the county.

It shows the first fire engine arrived within 10 minutes on 87.5 per cent of occasions in 2017/18.

The second was within 13 minutes on 89.1 per cent of occasions. And the third within 16 minutes on 88.7 per cent of occasions.

Although they did not meet the 90 per cent target, the IRMP – which will be discussed by councillors on Friday – concludes that stations are currently in “acceptable locations”.

However it does say they will “actively seek” opportunities to relocate fire resources to the most appropriate locations for the future.

“Our resources are currently well located to enable us to meet our emergency response attendance standards and to be part of the local communities we serve,” said the IRMP.

“However, Hertfordshire is predicted to see significant expansion in terms of both infrastructure growth and population and so HFRS must regularly reassess where it locates its resources and assets.”

Currently, according to information included in the IRMP, 89 per cent of Hertfordshire residents live in urban areas – which account for just 32 per cent of the county.

And 11 per cent of residents live in the remaining 67 per cent of the county, which is rural.

According to the IRMP there are currently just over  1.18million residents in Hertfordshire. But that’s expected to grow to 1.4 million by 2037.

A similar map in the draft IRMP also indicates some areas that could not be reached within the 12 minute target, following a call to a road traffic accident.

However the Service did exceed the road accident target – reaching 85.7 per cent of accidents within 12 minutes, compared to a target of 75 per cent.

On 96 per cent of occasions a fire engine reached an incident involving hazardous materials within 20 minutes – compared to a 100 per cent target.