Sprinklers saved a flat in a sheltered accommodation block in Barset Road, Southwark, from being severely damaged by a fire.
The fire started in a ground floor flat and a sprinkler system in the room where the fire originated extinguished the blaze before firefighters arrived.
A member of staff called the Brigade after hearing a smoke alarm sounding. Thankfully there were no reports of any injuries.
A London Fire Brigade spokesperson said: "Sprinklers are the only fire safety system that detects a fire, suppresses a fire and raises the alarm.
“They save lives and protect property and they are especially important where there are vulnerable residents who would find it difficult to escape, like those with mobility problems.”
The Brigade was called at 1036 and the incident was over for firefighters at 1115. Two fire engines from New Cross and Old Kent Road fire stations attended the scene.
The cause of the fire is believed to be accidental.