The report describes prolonged waits, overcrowded environments, a lack of privacy and unmet basic needs, which increase the distress and risk for patients, families and healthcare staff.

Nichola Crust, senior safety investigator at HSSIB, said: ‘Our investigation found that emergency departments are often caring for people in crisis in spaces that were not designed for prolonged mental health care. Long waits, limited privacy, unsuitable environments, gaps in information sharing and inconsistent approaches to care can increase distress and make it harder to understand and respond to a person's changing risks and needs.'

Staff described increasing pressure, burnout, compassion fatigue and moral distress associated with caring for people who require specialist mental health support in environments unsuited to their needs.

The report calls for the Department of Health and Social Care and NHS England to set out national minimum operational service standards and built design expectations for emergency departments.

It also calls for:

• clear expectations for roles, responsibilities and accountability for clinically appropriate, co-ordinated Mental Health Act assessment pathways
• effective shared care, governance and escalation arrangements and processes to identify, escalate and review delays related to assessment, bed availability and onward care
• arrangements to assess, plan for and assure the capacity, capability and resilience of the workforce, including access to relevant specialist and statutory professionals
• agreed measures and reporting arrangements to monitor workforce and pathway pressures, evaluate improvement actions, identify variation in access, waiting, experience, use of restrictive interventions, and address inequalities between population groups.

A Department of Health and Social Care spokesperson said: ‘It is unacceptable that people facing mental health crises have not been getting the care they need, when they need it, and that is why this Government is committed to transforming mental health services in our country.

‘We are rolling out 159 new mental health facilities to give people specialist care in their own communities, and later this year, our Mental Health Strategy will go further, outlining our plans to build a more integrated system that intervenes earlier and reduces waiting times so people can receive the right support when they need it most.'

The Government and NHS England are considering the recommendations from the report.