The 198 metre chimney came down in a controlled explosive demolition providing a spectacular show for onlookers who had been gathering well before its scheduled 11.15am demolition.

Four hours after the show, residents from the exclusion zone were given the all clear to return home.

Tests detected no asbestos south, south-west, south-east or east of the site, a special website set up for the felling of the stack said.

Dust was found to the east and south-east of the site but short-term exposure was "not considered to pose a risk to health".

Some locals had expressed concerns that the chimney hadn't been properly assessed for asbestos.

Wollongong City Councillor Vicki Curran moved an emergency motion this week to stop the demolition taking place, but the motion failed.

After the demolition, Ms Curran said strong vibrations had concerned some residents in the exclusion zone who were now worried about the structural integrity of their homes and water pipes.

The dust cloud was "significant and widespread" and "not being contained on site as we'd been previously assured by Port Kembla Copper".

Police began door knocking in the exclusion zone at 7.30am and residents were allowed to return just after 3pm