Call over 'Dickensian' loo policies
Union leaders have called on firms to give proper lavatory breaks to their staff after revealing that some workers are not supposed to go to the toilet during their shifts.
The TUC also complained that many employees had no access to toilets or had to use dirty, poorly maintained ones.
The union organisation first raised the problem in 2003 but said there had been little improvement since then, revealing that some employers believed staff should go to the lavatory in their own time.
Some workers, including firefighters, had no easy access to toilets, while in some workplaces, lavatories were closed at night, said the TUC.
Workers could develop health problems if they were not able to answer the call of nature, union officials said.
TUC deputy general secretary Frances O'Grady said: "Employers shouldn't be mean and penny pinching over their employees' need to use the loo. They should trust staff and let them take a few minutes away from their work if they need to go.
"Dickensian attitudes to toilet breaks have no place in the modern workplace.
"Employees should be free to go to the toilet in work time, and not have to raise their hands for permission as if they were back in school, or have their employers keep notes on how long or how often they go for.
"And when staff do get the loo, they have the right to expect clean, well-ventilated facilities."
The TUC said it had uncovered cases where supermarket checkout workers were not supposed to go to the toilet during their four-hour shifts, while some traffic wardens have to inform managers if they go to the lavatory, and then record it in their pocket book.