Spending a penny is not just a polite euphemism for some employees.

Staff at Dunbia’s Sawley-based meat processing plant have to clock out every time they need to relieve themselves. This means they are not paid when they go to the toilet.

The company has confirmed that the measure is in place for safety reasons and that its workers are paid an additional bonus to compensate for their toilet breaks. This arrangement was implemented by the company five years ago and applies to hourly-paid members of staff.

However, according to union Unite more than 100 workers at the meat firm have made complaints about the policy. Unite is concerned that the measures are putting the health and dignity of workers at risk, and is urging Dunbia to reverse it immediately.

Cathy Rudderforth, Unite regional official said: "Basically, Dunbia is making money every time a worker visits the loo - and that money is coming out of the workers' wage packets. It's outrageous that in 2009 workers have to endure the indignity of clocking out for toilet breaks."

A statement from Dunbia read: "Employees are required to clock in and out when accessing and leaving major food processing production floor areas, including visiting the toilet, to ensure their safety and wellbeing on site.

"To ensure that employees do not suffer financial disadvantage, Dunbia (Sawley) increases employees’ weekly wage to compensate for toilet breaks. Employees are paid this additional allowance, even where they do not use the time allocated for toilet breaks."