The grandmother of a teenager who died after falling from a multi-storey CBD car park while texting a friend has called for safety barriers to be installed.

Ryan Robbins, 19, was escorting two young women to their vehicle in the car park, on the corner of Russell and Bourke streets, around 1.15am last Friday when the tragedy occurred, Patricia Schroeter said.

She said Mr Robbins, who worked at a meat-processing plant in Colac, had been at a work function and then a nightclub.

He had been drinking but was not drunk, Ms Schroeter said, and had wanted to ensure the women, who he did not know, were safe.

"Then he was texting his mate, unfortunately they separated, to find out where they were so he could meet up with them and get in the car and go home," she told radio 3AW.