CCTV footage has revealed the frantic moments after a freak explosion in Brabham left a young man seriously injured.

Lachie Perrem was at home on Thursday afternoon when a robotic vacuum exploded in the kitchen, leaving him fighting for his life.

Vision from a home security camera across the road captured every second after the blast including someone desperately warning Mr Perrem who had run back inside the home to “get out”.

But it was too late by then. Mr Perrem had already suffered significant burns with the video showing his desperation as he runs across his driveway screaming, “Help! Help!” moments after the blast.

The 25-year-old can be seen staggering through the street with his clothes burnt off and his skin scorched.

His screams were eventually replaced by sirens as fire crews flooded the cul-de-sac.

“Currently have one casualty on the lawn, administering first aid . . . burns to 80 per cent of the body,” is what could be heard over the firefighters’ radios.

Neighbour Rylee Davies told 7News they were putting Mr Perrem into an ambulance as he walked into his driveway.

“It’s quite a shock and a bit of a scare, to be honest. It can happen anywhere, really, in anyone’s home,” he said.

Mr Perrem is still unconscious and fighting for his life in the Fiona Stanley Hospital burns unit after undergoing multiple surgeries.

The explosion also left the rental he was living in with his fiancee and two housemates in ruins.

The kitchen and living room is unrecognisable as the blaze blew out windows and blackened walls.

Fire investigators are blaming the blaze on a fault in a robotic vacuum cleaner with the size of the explosion still under investigation.

The blaze has shocked the WA community including Premier Roger Cook who said his “thoughts were with him and his family”.

A GoFundMe has been set up to help Mr Perrem financially. The page has so far raised more than $22,000.