The mining giant, chaired by billionaire Andrew Forrest, is also opposed to the creation of an independent body to oversee the management of harassment claims.

FMG's stance is at odds with fellow Pilbara giants Rio Tinto and BHP, which have both indicated support for an industry-wide register which could help to prevent known offenders from picking up work elsewhere in the sector.

Facing a WA parliamentary inquiry, chief executive Elizabeth Gaines on Wednesday said FMG had investigated 11 sexual harassment matters in 2020 and a further 31 so far this year. Six workers had been sacked and others had faced lesser disciplinary action.

Ms Gaines said FMG did not share information with other miners about problematic workers and did not believe a register of offenders was appropriate.

"I think one of the challenges ... is who would regulate that, how long does somebody stay on the list, what happens if there's a mistake and they appear on a list through error," she said.

"There's a whole range of issues associated with that. Our preference is to adopt our approach which is to make sure we're recruiting in accordance with our recruitment practices."

About 30 per cent of respondents to a recent online survey of 2000 staff said they had witnessed sexual harassment or inappropriate behaviour at FMG sites.

The company said it was working to improve safety procedures at fly-in, fly-out camps including enhanced lighting, CCTV and the rollout of women-only gyms.

It will also soon introduce a on-site limit of four mid-strength drinks over a 24-hour period.

Unions have called for the mining industry to fund an independent body to manage sexual harassment claims.

But FMG's director of people Linda O'Farrell said the priority should be to streamline reporting for victims.

"Working directly with people who have made complaints to us, it is very daunting to them when we need to explain they may be contacted by somebody they don't know from a department that they don't have involvement with," she said.

"Having to tell a distressing story many different times to people that they do not know, that in itself can be a very traumatic situation."

Rio Tinto's iron ore chief Simon Trott said he was sickened by the evidence of widespread sexual misconduct within the industry.

Since the start of 2020, Rio has identified one substantiated case of sexual assault and 29 sexual harassment cases. About 15 workers have been dismissed, while others remain under investigation.

Rio is looking to roll out expanded psychometric testing for potential recruits.

"It's certainly an area that we're looking at as a predictor of future behaviours," Mr Trott said.

BHP last week said it had sacked at least 48 workers for sexual misconduct over the past two years.

Australian Associated Press