Seven in 10 NHS hospital trusts in England are failing to meet national safety standards, it has been warned.
An Observer analysis of inspection reports reveals staff shortages are the biggest problem.
Reports by the Care Quality Commission (CQC) show managers at one trust failed to act on staff reports of abuse and violence, while a shortage of critical beds at another trust led to three serious incidents resulting in patient harm.
Of 148 acute and general hospital trusts, safety standards at 96 are rated as requires improvement by the CQC and six are rated inadequate, the lowest category. The others are rated good, with none outstanding.
Of the 14 inspection reports published since the start of June, half raised concerns over inadequate staffing levels.
Rob Harwood, chair of the consultants committee at the British Medical Association, said that with the NHS chronically underfunded and understaffed for many years, staff are increasingly expected to deliver care in an unsafe, unsupportive environment, putting the safety of patients at risk.
A Department of Health and Social Care spokesperson said: “There are 16,800 more nurses on our wards than in 2010 with 52,000 more in training and to help retain our dedicated staff we are providing more flexibility and career development alongside multi-year pay rises for junior doctors and over a million other NHS workers, including nurses.”