Incredibly no-one was injured in the incident, which saw seven roads in Hook evacuated in the early hours of Wednesday.
Fire fighters first thought they were dealing with a caravan fire until they were told it was next to a transit van containing acetylene.
“Acetylene is a big problem, especially when it has been heated up,” said Mike Gates, public relations manager for Hampshire Fire and Rescue Service, as he surveyed the charred remains of the caravan on Wednesday morning.
“There are standard procedures where acetylene is involved, including the evacuation of everyone within 200 metres.
“We had to evacuate between 120 and 150 people from around 40 homes.
“There are about ten homes in the cul-de-sac where the fire was but there are a number of other cul-de-sacs that back on to it.”
Firefighters from Basing-stoke, Odiham and Hartley Wintney were called to the caravan blaze on the driveway of a terraced home in Oak Tree Drive at 4.23am.
The family caravan, which contained propane butane gas cylinders, was totally gutted.
In front of it was the works van, which contained oxygen, acetylene and argon gas cylinders, which was badly damaged, as was the family Toyota people carrier parked beside it.
The remains of two charred baby buggies could be seen sticking out of the boot of the car.
“The owner of the house runs a mobile maintenance company for commercial vehicles which involves welding work so he had a lot of gas cylinders in the van and the garage,” said Mr Gates.
“I spoke to him at about 7am and he was obviously still shocked.
“We have the Fire Victim Support Unit here and they were helping him contact his insurance company and tracking down his insurance policies.”
Cars either side of the house were also damaged by the fire.
“The bedroom over the garage was smoke damaged and so was the next door neighbour’s bathroom,” said Mr Gates.
People in Alderwood Drive, Hawthorn Rise, Beechcrest View, Ashlea, Oak Tree Drive, Birch Grove and Hazel Copse were evacuated to the nearby Raven Hotel, where the WRVS provided hot drinks.
At 10.50am, Geoff Eddy from Hampshire County Council’s emergency planning team told residents they would soon be going home.
“The incident is being scaled down and hopefully you will be able to go back and have lunch in your own homes,” he told the anxious residents.
“I apologise that you were so rudely interfered from your sleep this morning but you must bear in mind it was for your own safety.
“It could have easily gone the other way and if the acetylene had exploded it would have caused a bomb-like effect.”
Mr Gates said: “The normal procedure is to let the cylinders cool off for up to 24 hours but we are happy they are now safe enough to move.
“However we are now waiting for the gas experts to arrive from Reading to give the all clear.”
Fire investigation experts will then sift through the charred remains of the caravan to find out what caused the blaze.