Heated scenes as Conroy takes on Morrow

Heated scenes broke out at a senate estimates hearing when a Labor senator made a critical remark about the head of the national broadband network.

"People died last time you were in charge of something," the opposition's Stephen Conroy shouted at CEO Bill Morrow during a hearing in Canberra on Tuesday.

Mr Morrow previously oversaw an American company, which later had two of its pipelines explode, killing nine people.

Committee chair Linda Reynolds described the remark as unparliamentary, inflammatory and highly insulting, and asked Senator Conroy to apologise.

He initially refused, but did so after a short private meeting between committee members.

Mr Morrow also agreed to apologise to Labor's Deborah O'Neill, who had been asking questions about the rollout on the NSW Central Coast at the time.

"I withdraw. I would never speak down to a senator," he said.