A receptionist in London was sent home from work for refusing to wear high heels.

Temp worker Nicola Thorp says she arrived at her first day on the job at a finance company and was told she couldn't wear flats on the job. Instead, she was told to go out and buy shoes with 2-inch to 4-inch heels or be sent home without pay.

"I said 'If you can give me a reason as to why wearing flats would impair me to do my job today, then fair enough', but they couldn't," she told BBC London. "I was expected to do a nine-hour shift on my feet escorting clients to meeting rooms. I said I just won't be able to do that in heels."

Thorp asked if a man would be expected to do the same job in heels and says she was laughed at. When she refused to wear heels, she was sent home.

This happened in December, but Thorp said she has since talked to friends about it and posted on Facebook and realized it has also happened to other women. That prompted her to petition the government, asking for the law to be changed.

Currently, U.K. employers can dismiss workers who don't comply with "reasonable" dress code demands, according to the law firm Thompson Solicitors. Employers are allowed to set up different rules for men and women as long as there is "an equivalent level of smartness."

In Thorp's case, Simon Pratt, the managing director of Portico, the temp agency that hired her, said she had signed the appearance guidelines before starting work. But Pratt said Portico is now reviewing its policies.

Nicola Thorp Although Nicola Thorp was sent home from work in December, she filed the petition recently after realizing other women had experienced the same issue. (Photo: Nicola Thorp/Facebook)

Thorp's petition reads:

It's still legal in the UK for a company to require female members of staff to wear high heels at work against their will. Dress code laws should be changed so that women have the option to wear flat formal shoes at work, if they wish. Current formal work dress codes are out-dated and sexist.

The petition currently has more than 25,000 signatures. The government must respond to any petition with more than 10,000 signatures, so the petition will be considered for debate in Parliament.

"I was a bit scared about speaking up about it in case there was a negative backlash," Thorp said. "But I realised I needed to put a voice to this as it is a much bigger issue."

A dress code that requires women to wear high heels "reeks of sexism," Frances O'Grady, general secretary of the TUC, Britain's trade union, told the BBC. "High heels should be a choice, not a requirement."

High heels are also a health concern. They can lead to stress fractures, sprains, fractures, bunions, hammertoes and more, according to the American Orthopaedic Foot & Ankle Society.

"Twenty years ago, women weren't allowed to wear trousers in the same role that I'm doing now, and it's only because some women spoke up about that and said 'We feel like we have a right to wear trousers' that that's changed," Thorp said. "I think that dress codes should reflect society, and I don't think that this particularly loophole in the dress code policy does reflect modern society in any way."

Mary Jo DiLonardo Mary Jo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.