FIREFIGHTERS were called to more than 150 fires in sheltered housing complexes throughout Kirklees last year.
And worried fire chiefs have revealed their concern that a quarter were started on purpose.
The shock figures emerged on the day a sheltered housing complex in the Holme Valley unveiled its own sprinkler system.
The sprinklers have been fitted into Roundway Sheltered Housing in Honley along with a new fire detection system, emergency lighting on escape routes and new fire doors to stop any fire from spreading through the building.
Nigel Charlston, Senior Fire Safety Officer for the West Yorkshire Fire and Rescue Service, said: "Fires in sheltered housing have become more of a problem in recent years in West Yorkshire.
"In 2003-2004 we dealt with 771 sheltered housing fires in the county, 152 of which were in the Kirklees district. Shockingly, just under a quarter of these were started deliberately.
"In a project like this, the residents are given more chance of surviving a serious fire and less damage is caused when the sprinkler systems come into effect.
"One of our priorities at the moment is to work with vulnerable groups such as the elderly and this is a prime example of the kind of thing we hope to see more of."
Brian Mellor, crime and fire prevention co-ordinator for Kirklees Neighbourhood Housing, said: "Fire safety is a concern to elderly residents and they have welcomed the fire precautions carried out for their safety, offering their support throughout the process."
The fire service now wants to see domestic sprinkler systems in all new and refurbished sheltered housing projects.
Figures show that nationally the average property loss in homes protected by sprinklers is 38% lower than homes without sprinklers.
Heat from a fire activates the sprinklers which automatically switch on to douse the flames.