INSPECTORS found people were regularly treated in corridors and hazardous substances were left in unlocked rooms after spot visits to Colchester Hospital.
The Care Quality Commission (CQC) audited the hospital’s medical care and urgent and emergency care in Turner Road in April this year.
Both assessments were triggered by concerns raised by either patients or family members.
The report, published on Wednesday, found hospital care required improvement.
The damning report said safety of medical care and safety of emergency services were both downgraded to inadequate.
The report highlighted breaches of standards relating to safe care and treatment were recorded during the visit, there was poor compliance with infection prevention, control measures and use of personal protective equipment.
Low staffing levels caused delays in care, and breaches were observed in safeguarding and consent procedures.
This also resulted in low morale among staff, not helped by frequent moves between wards.
Further, the report highlighted patients and their families with inadequate communication.
Mental health patients were experiencing especially long waiting times, as one patient waited more than 100 hours before being admitted to a mental health bed in the emergency department.
Staff were not always sufficiently trained to deal with cases, the CQC stated.
Hazel Roberts, CQC deputy director of operations in the East of England, said: “When we inspected Colchester Hospital, we continued to find concerns about how people were cared for.
“Some of these are the same concerns we’ve already highlighted at previous inspections.
“We’ve also found new concerns about the deterioration in the safety of these two services in particular.
“In urgent and emergency services, the department was very crowded, with people regularly treated in corridors. People said staff were kind and we saw they worked hard to meet people’s needs, but these spaces gave people little privacy or dignity.
“While most people said they felt safe and understood their treatment, others, particularly older people and their families, said they weren’t given clear discharge plans. Healthwatch and local health and social care providers raised similar concerns about communication when people left hospital.
“Leaders at Colchester must ensure they are using the findings from CQC’s reports and putting in place effective systems enabling them to fully understand the issues and work together to drive and sustain improvements.
“We’ve shared our findings with the trust so they know where improvements must be made.
“We’ll continue to monitor both of these services closely to ensure people receive safe care while these improvements are being made.”
Nick Hulme, the chief executive of the trust which runs Colchester Hospital, said action has been taken to address the areas identified for improvement.
He said: “Delivering safe, high-quality, and compassionate care remains our top priority.
“While the CQC’s findings are a clear reminder of where we must do better, they also reflect the incredible, ongoing efforts of our staff.
“This report reflects a point in time. A significant amount of work has taken place since the inspection in April. We are determined to build on that progress and to make sure every patient receives the best possible care.
“I want to thank all our teams for their ongoing dedication and compassion. I would also like to reassure our communities that we remain focused on delivering the safe, high-quality care they rightly expect.
“We will continue to act with urgency and determination to improve. We are absolutely committed to providing the best possible care for our patients and their families every day.”