West Yorkshire Fire and Rescue, which covers one of England’s biggest cities, Leeds, was hardest hit, losing 70 per cent of its inspectors since 2010, freedom of information requests by the Fire Brigades Union (FBU) show.
And fire services in Gloucestershire, Durham, Cumbria, Norfolk and Avon all lost more than half of their fire safety specialists.
The real figure could be much higher as some fire and rescue services didn’t even know how many inspectors they had in 2010, said the union.
The crucial inspectors are responsible for ensuring that communal buildings such as Grenfell Tower and public spaces meet fire safety standards.
FBU general secretary Matt Wrack said: “Fire safety specialists play an essential role in the fire service.
“They help to enforce fire safety regulations that save lives and prevent damage to property. Fire services need proper funding, more inspectors and greater support if they are to continue keeping people safe.
“Grenfell Tower has underlined the importance of fire safety in buildings. The drastic cut in fire safety inspectors makes it much more difficult for those remaining to do their job effectively.
“The government needs to wake up to what endless budget cuts have done to the lifesaving fire service.”
In Scotland, firefighters are checking two private tower blocks in the Glasgow Harbour development “every four hours” over fears they are built with the cladding material used on Grenfell.