A fire broke out and was quickly extinguished Monday night in a crude distillation unit at Chevron Corp's 245,271 barrel-per-day (bpd) Richmond, California, refinery, according to notices the refinery filed with state and federal pollution regulators.

Chevron spokesman Sean Comey confirmed there was a fire at the refinery Monday night that sent a worker to a hospital with minor injuries.

Comey did not identify the unit involved in the fire.

We continue to supply products to our customers without interruption, he said.

West Coast refined market traders said they understood the fire was minor and the crude unit was returning to normal operation on Monday morning.

The San Francisco Bay wholesale gasoline market may firm up on the psychological affect with Chevron not putting out the full impact of the fire, said a trader who asked not to be identified by name so as not to affect possible future dealings with Chevron.

The fire broke out shortly before 6 p.m. local time Monday (0200 GMT Tuesday) as the crude unit was being started, according to the notice filed with the California Emergency Management Agency.

A crude distillation unit does the initial refining of crude oil coming into a refinery and provides feedstock to all other units at the refinery.