A 67-year-old man suffered burns to his head and neck after a dust explosion in a malt drying vessel.
Firefighters gave him first aid while waiting for paramedics to arrive at the scene, Bairds Malt, Station Maltings, Witham.
The casualty was left in their care.
Crews used one hose reel to tackle the fire in the factory unit, measuring 10m x 30m.
The incident was reported at 2.05am today and was dealt with by 3.07am.
A fire investigation will be carried out to establish the cause.