A new sprinkler system is being installed in two tower blocks as a safety measure in response to the Grenfell Tower fire.
The mist-style devices are among a £4.5m package of improvements at Leabank and Penhill Flats on Luton's Marsh Farm estate.
Residents said they felt "safer" and "more protected" because of the work.
It started in August and should be completed by February, covering 14 floors.
Abdul Kahir, housing asset manager for Luton Borough Council, which maintains the buildings, said: "It is about making sure that people living in high-rises are given assurances they are safe.
"We are a forward-thinking organisation, and have invested quite a lot of money over the years to improve our properties."
The improvements also include:
- Solar panels on the roofs to power communal lights and a CCTV system
- A concierge
- New external cladding and insulation
- Replacing communal windows and smoke vents
- Heat recovering ventilation systems in all flats
One of the main additions is a brand new Automist Smartscan system which according to Mr Kahir is "new to the market" and a "better system to have."
He said it was a type of directional sprinkler that suffocated the oxygen instead of drenching a room with water, meaning it could cause less damage to properties.
Elvan, who lives in one of the flats with one child, said she was "very happy" with the work, as she believed they were "safer and more protected".
Another resident, Bachunaman Begom, also said he felt safer.
The work was due to start in the summer 2017, but after the Grenfell Tower fire, the council carried out extensive tests on the cladding and insulation due to be put on the building to make sure they were safe.
The mist system was then earmarked for installation as an "additional measure", they confirmed.