NORTH West Aerosols Ltd is a company that puts gas into aerosol canisters and employs a workforce of around 40.
One of the firm's directors spent this morning at the site of the blast helping the fire service with their investigation.
The cause of the explosion is still unclear as the company had installed specialist safety features on site.
THE WITNESS
ERIC Swift, who works at the Express Dairies depot, around 200 yards from Northwest Aerosols, said: "There was one big explosion. I was inside but could hear it very clearly.
"Then there were several big bangs. I came outside to see what was going on and there were flames licking the side of the building. One of our lads called 999."
THE FIREFIGHTERS
ALEX McDougal, spokesman for Mersey Fire and Rescue Service, said: "After the first explosion, fire took hold in the building which led to a series of subsequent explosions of aerosols.
"Three teams of firefighters were deployed inside the building who quickly led three men to safety outside.
"The leak happened at one end of the factory where staff work by putting gas into the aerosols.
"Propane is highly flammable and explosive when contained which is what has happened here."
John McDonough, Liverpool district manager of Mersey Fire and Rescue Service, said: "We are still trying to establish the cause of the blast. There is nothing at this stage to suspect this is a suspicious incident."