Nurse / midwife to patient ratios
Nurse/midwife to patient ratios (ratios) are the minimum number of registered nurses, midwives, and enrolled nurses working on a particular ward, unit, or department, in relation to the number of patients on the ward.
Minimum ratios are applied for every shift (morning, afternoon, night) and may not be the same for each shift or every clinical area.
The implementation of ratios commenced with a successful pilot in the Perth Children’s Hospital Emergency Department in July 2023.
Following this, ratios has been introduced in a phased approach across medical and surgical wards, and critical care areas, at the Child and Adolescent Health Service, East Metropolitan Health Service, North Metropolitan Health Service and South Metropolitan Health Service.
What are ratios?
A complete list of wards/units and their allocated ratio category can be found on the Nurse/Midwife to Patient Ratios: Wards/Units in Scope for Implementation document.
Why is WA moving to ratios?
WA Health is committed to maintaining a contemporary workload management methodology that strongly aligns with the principles of evidence-based safe staffing.
Clause 10 of the WA Health System – Australian Nursing Federation–Registered Nurses, Midwives, Enrolled (Mental Health) and Enrolled (Mothercraft) Nurses Industrial Agreement 2024 (ANF Agreement) and Clause 12A of the WA Health System – United Workers Union (WA) – Enrolled Nurses, Assistants in Nursing, Aboriginal Health Workers, Ethnic Health Workers and Aboriginal Health Practitioners Industrial Agreement 2024 (UWU Agreement) commits to transition from Nursing Hours per Patient Day to ratios over a minimum of 2 years.
What will happen to Nursing Hours per Patient Day?
Until ratios are implemented in a specific ward/unit, Nursing Hours per Patient day (NHpPD) will continue to be used as the primary workload management methodology. Once ratios are implemented across all wards/units, NHpPD will no longer be used.
Day to day operations
The way patients are cared for will remain unchanged, with patient care and staff wellbeing remaining the priority. In areas where the NHpPD classification level is higher than the minimum ratio, the higher staffing level will be retained.
The number of patients assigned to each nurse/midwife can differ depending on clinical need, provided the overall minimum ratio for that ward/unit is met.
Patient allocations will continue to be based on acuity and remain responsive to the activity of the ward/unit/department.
More information
The Nurse / Midwife to Patient Ratios Policy outlines requirements for implementing ratios.
Last reviewed: 17-09-2026