Three fire engines and around 15 firefighters tacked a fire at a disused portable cabin in Stockley Road, West Drayton.
The cabin was destroyed by the fire. Two gas cylinders were removed and cooled to ambient temperatures, as gas cylinders can explode when exposed to heat.
There were no reports of any injuries.
The Brigade was called at 1633 and the fire was under control by 1745.
Fire crews from Heathrow, Hillingdon and Feltham stations attended the incident.
The cause of the blaze is under investigation.