The cleaning company said it was independently audited

Patients and workers for a private cleaning firm claim there are too few cleaners to cope and working conditions at Derriford Hospital in Plymouth are intolerable.

But hospital managers and the company in charge of cleaning insist it has a model record for cleanliness and infection rates are kept to a minimum.

[Toilets] are cleaned in the morning, and that is it Michael Stone

Patient Michael Stone, 61, from Cornwall, has pledged never to return Derriford.

He has been treated on several occasions but says he has no confidence the hospital is clinically clean on a consistent basis, using the toilets as an example.

He said: "They're cleaned in the morning, and that is it.

"So, at night times, a lot of people are disorientated, many are elderly, some of them are incontinent.

"They go to the toilet, dribble on the floor and you have to go and stand or sit in that, and it's not acceptable."

The BBC spoke to an employee of ISS Mediclean, the private company contracted to provide cleaning and other services.

She said staffing levels are so low that, during weekends and evenings, one member of support staff often oversees two wards.

The infection control team ...works tirelessly to ensure infection rates are kept to their lowest Christina Quinn Nursing director

She says the feeding and cleaning of scores of patients should be the job of six people.

She said: "One girl over the summer went home and collapsed on the Saturday night because she just couldn't cope in the ward on her own."

ISS Mediclean said it was "confident that sufficient time is allowed for all duties to be completed".

It continued: "This is borne out not only by our own monitoring but by the independent audits, such as the recent Patient Environment Action Teams (PEAT) visit, which awarded the hospital 'green status', the best available. "

Managers at the hospital also say the hospital is clean and levels of cross-infection or MRSA are no worse than any other big hospital.

Assistant Director of Nursing Christina Quinn said: "The trends for MRSA in this trust look as if they are decreasing.

"That's a really positive thing, particularly for the infection control team, which works tirelessly to ensure infection rates are kept to their lowest."