Union boss Kathy Jackson says she’s glad she’s had her day in the royal commission and has defended the “war chest” she set up as necessary to her work.

Union boss Kathy Jackson says she is glad she has faced the royal commission into union corruption despite revelations she set up a slush fund with union money and accessed it for personal spending.

The Health Services Union national secretary said she was “totally relieved” as she left the commission on Thursday.

“I’ve had three years of total hell with the Health Services Union,” Ms Jackson told media.

“I’m very glad that I’ve had my day in the royal commission.

“I have three young children at home and finally I can get on with my life.”

Ms Jackson blew the whistle on rampant corruption by now-jailed HSU general secretary Michael Williamson and has detailed extensive intimidation by union officials intent on discrediting her.

However, the commission heard that Ms Jackson set up an unaudited fund, the National Health Development Account (NHDA), using a $250,000 payment to the union and used it as a slush fund, or as she put it, a fighting fund for union campaigning and administrative expenses.

Ms Jackson also said she was authorised to use $4000 a year for personal expenses, in addition to a $270,000 salary, to cover her long working hours and attendance at committee meetings.

The union boss, who has been on sick leave since 2012, defended the fund and her personal use, which included doctor’s bills and tuition fees.

“I think I’ve done well out of the royal commission – I’ve got nothing to hide,” she said.

Ms Jackson told the commission that she understood that the public may find the practice of keeping a fighting fund like the NHDA “unpalatable”.

“It may fall short of proper practice in relation to what the public would expect but I don’t say it’s an illegal account,” she said.

She said the NHDA was necessary in order to effectively perform her work.

“In order to be able to survive in that political environment you have to have a war chest,” she said, adding that “factional warlords” were always on the hunt to take over other unions to secure their membership base.

“You have to have money in an account such as the National Health Development Account to be an effective union leader.”

Ms Jackson said it was common business practice among unions.

“I understand that the majority of the public or members of the community would find this unpalatable but let me say this again, this was how business was conducted not just in my organisation but across the movement,” she said.

Under questioning, Ms Jackson was unable to recall details of fund transactions, including transfers to the fund of $50,000 and two transfers of $8000.

Ms Jackson has told the commission she kept all her records of NHDA spending in an exercise book that disappeared after her office was ransacked in 2011.

She said her union enemies had taken the book “because it would embarrass a lot of people about what’s in there and where the money went”.

Ms Jackson said she was committed to cooperating with the commission and hoped it would deliver effective reform to the union movement.

The hearing continues in Perth on Monday.