Man critical after SA factory explosion

A man is fighting for his life in hospital after suffering serious burns in a factory explosion in Adelaide's north.

The 29-year-old sustained burns to his upper body in the incident at Edinburgh on Monday night and remains in a critical condition at the Royal Adelaide Hospital.

He and another employee, who also suffered burns, were working with a chemical when it ignited just after 7pm, authorities say.

Safework SA is investigating the incident.