About 30 firefighters were called to a fire under a sulphur vat at the Shell plant in Lower Hutt this afternoon.
A Fire Service spokeswoman said staff at the plant activated a deluge system to try and extinguish the fire in the suburb of Seaview. Firefighters arrived and put the blaze out.
Crews from 10 fire engines – including a specialist engine for staff with breathing apparatus, a command unit and an engine allowing an aerial attack – were used. Firefighters were still at the scene after 3pm but the fire was under control.