Half of nurses are working through breaks or beyond their shift, revealing a health service under "severe strain", a new report has warned.
A survey of almost 3,000 nurses by Unison showed that two thirds believed they didn't spend enough time with patients, which most said affected care.
Three out of five of those questioned felt that staff numbers led to lower standards of care, while almost half said they were looking after eight or more patients.
The report, Running on Empty, said half of nurses were not confident about raising any concerns they had with their local managers
Gail Adams, Unison's head of nursing, said: "One of the most damaging findings of this survey is how little has changed since last year. Despite all the government rhetoric, despite the Francis, Keogh and Cavendish reports, the spectre of another Mid Staffs still looms large over the NHS. Progress on safe staffing levels has been glacial and that means poorer care and patients still at risk.
"It's clear that despite nurses working through breaks and beyond their hours, they simply do not have enough time to give patients the care and attention they need. That is distressing for patients and for the staff trying to care for them.
"The Government needs to face up to the damage it is inflicting on patients and staff, by not introducing legally enforceable nurse to patient ratios, and take urgent action."
The union claimed that the survey also revealed an "over use" of agency staff in the NHS.
In another study last week, Unison said the ambulance service was on the verge of breaking down because of stress levels among staff.
The issues will be debated at Unison's health conference in Brighton, which opens today.