Emergency Management Victoria Commissioner Andrew Crisp has maintained the Australian Defence Force didn't offer personnel for the program at a meeting on March 27, nor did he ask for their help.

"We believed that we had the resources within the state to meet the needs of that particular program," he told the Public Accounts and Estimates Committee's COVID-19 Inquiry on Wednesday.

Mr Crisp said the decision to use private security guards was made at the same meeting, although talks had already begun with contractors.

"Work had already been undertaken to plan for hotel quarantine," he said, noting the program began the following day.

The inquiry previously heard the Department of Jobs, Precincts and Regions was responsible for awarding contracts to three security companies: MSS, Unified and Wilson.

When asked if Victoria Police assistance was offered to guard returned travellers Mr Crisp replied: "that was not part of the discussion".

About 99 per cent of Victoria's second COVID-19 wave can be traced to three outbreaks at the Rydges on Swanston and Stamford Plaza hotels.

In late May, when the virus first broke out of the hotels, 19 people in Victoria had died from COVID-19. The state's death toll is now 462.

Victoria Police Chief Commissioner Shane Patton said criminal inquiries are underway into security companies engaged for the program.

"Last week, I was made aware that complaints had been made to the licensing and registration division which govern that area," he told the inquiry.

It is unclear which companies are being investigated.

Meanwhile, the Department of Health and Human Services and Department of Jobs, Precincts and Regions are among 20 duty holders being investigated by WorkSafe for COVID-19 breaches.

Both departments had a key role in the hotel quarantine program.

WorkSafe chief executive Colin Radford told the inquiry the work practices of security companies at eight workplaces are also under scrutiny.

But Attorney-General Jill Hennessy stressed occupational health and safety investigations were common.

"If you put COVID aside, healthcare is again one of the highest-ranked occupational health and safety areas of risk," she said.

"Government is not immune from occupational health and safety laws. Government is investigated when there is a suggestion or a complaint or a potential assertion of a breach of a duty and that is the way it should be."

Ms Hennessy sought to distance herself from the program, telling the inquiry she played no part in setting it up or the decision to hire private security guards.

"I did not bear any ministerial role in the establishment of hotel quarantine so I can't really speak to those early decisions," she said.

The program is now being overseen by Corrections Victoria.

Earlier this month the responsibility for the program was transferred from Health Minister Jenny Mikakos to Ms Hennessy, who held the health portfolio between 2014 and 2018.

WorkSafe inspectors have visited 873 high-risk worksites over the past five weeks and issued 196 notices to businesses not complying with coronavirus restrictions.

About 23 per cent were found to not be complying with "overall" restrictions, 17 per cent not complying with strict cleaning regulations and 14 per cent not appropriately maintaining physical distancing.

It was also revealed 19,800 individuals have been fined for breaching coronavirus restrictions since the start of the pandemic, including for not wearing face masks and breaching curfew.

Some 1108 of those fines are under review.

Australian Associated Press