Shannon has been delivering parcels for 18 years, but she still has customers telling her she shouldn't be doing it because "it's a man's job".

Tayla had people tell her "girls shouldn't be on work sites" when she was working as a roofer right up until she had her daughter last year.

Teagan says she has experienced "every sexist joke under the sun" from customers while working at a mechanic shop.

The three women work in different industries around Australia. They say they are massively supported by their employers but they still see attitudes of sexism in the greater community, perpetuated through old-fashioned stereotypes of what constitutes "a woman's job".

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'Girls on the job, something will go wrong'

Shannon Menzies, 40, told 9news.com.au that her employer of nearly two decades, Couriers Please, had been great at supporting her as a woman and a mother.

The Brisbane woman, who runs a Couriers Please franchise, said the company had been very understanding of her need to juggle work and caring for her children, allowing her flexibility with her schedule.

"Especially because for a period there was a single mum, so they knew my children needed me."

But she said she still often delivers to customers who express surprise that she's not a man.

"They say, 'You shouldn't be doing this for a job. This is a man's job'," Menzies said.

She said she also regularly has people ask her, "How do you carry that?"

The comments have become much more frequent since she fell pregnant with her third child.

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