By Liz Stephens
Delegates at the TUC congress are being urged to back a motion requiring some employers to carry out risk assessments on their workers' footwear.
The controversial motion has come about because some union members claim workers are forced to wear high heels as part of their dress code - which can lead to chiropractic problems.
Unions are calling for firms to examine the risks that employees wearing high heels can face and replace such policies in favour of "sensible shoes", where appropriate.
The motion says: "High heels may look glamorous on the Hollywood catwalks but they are completely inappropriate for the day-to-day working environment.
"More needs to be done to raise awareness of this problem."
It recommends a broad heel (no stilettos) which is no higher than 4cm, and "if worn for long stretches, no higher than 2cm".
The Society of Chiropodists says two million working days a year are lost to leg and foot injuries - many caused by high heels.
A spokesman for the society Eddie Saville said: "This is a serious issue for women in the workplace".
However, some unions are opposing the move as restricting freedom of choice for women.
They have received the unlikely backing of Tory MP Nadine Dorries who has even said that the extra height given by heels can help women in the workplace.
"If high heels were banned in Westminster, no one would be able to find me," she told the Daily Mail.
"The TUC need to get real, stop using overtly sexist tactics by discussing women's stilettos to divert attention away from Labour chaos."
Major airlines and some well-known city banks have a heels-only dress code for women.