The NSW Hazardous Materials Response Unit (Hazmat) was called in to deal with the spill of hydrocloric acid in Warialda Street after a black container fell off the back of a truck.

Police closed the road for an hour from 2.30pm, causing traffic congestion in the surrounding area and preventing people arriving home from getting on to the street.

Tony Steele, station officer at Hurstville fire station, said the spill could have caused burns or respiratory problems for anyone who came into contact with it.

"We prevented it from entering the drains," he said.

"It came out of the 10 litre drum and ran down the road for about 20 metres.

"It looks like just an accident, it's fallen off a truck."

Two members of Hazmat wore chemical protective suits to clear up the acid.

Sudsir Kunwar, a university student who lives on Warialda Street, who could not get into his house, said: "I just finished university and I couldn't get home. I was told to wait."