Four fire engines and around 25 firefighters were called to a flat fire on Lancelot Road, Wembley.
Half of the ground floor lobby and part of two ground floor flats were damaged by the fire.
One person was led to safety wearing a smoke hood by crews wearing breathing apparatus. They were then treated by London Ambulance Service for smoke inhalation. Seven other people left the property prior to the brigades’ arrival.
Fire escape hoods provide members of the public with up to 15 minutes protection from four of the main fire gases (carbon monoxide, hydrogen cyanide, hydrogen chloride and acrolein) and can be worn by conscious or unconscious people. If more than 15 minutes protection is required, then another hood can be given to each wearer. They do not provide oxygen but temporarily filter toxic smoke to make breathing easier.
Control Officers took the first of nine calls at 1731 before mobilising crews from Ealing and Brent fire stations to the scene. The incident was under control by 2127.
The cause of the fire is under investigation by London Fire Brigade.