Content Update: Isolation Rooms - Engineering and Design Requirements

Date published 09/04/2026

An updated revision of the AusHFG resource Isolation Rooms – Engineering and Design Requirements (Revision 2.0, April 2026) has been uploaded to the AusHFG website.  This updated version describes the engineering and design requirements for isolation rooms used to manage patients who require transmission-based precautions or protection from external sources of infection. The guideline describes the various types of isolation rooms and best practice design features, as well as commissioning and ongoing maintenance considerations. The revised version has been informed by extensive consultation with engineering and design experts, clinicians and infection prevention and control specialists.

Key changes to the document include:

  • Revised information on the types of isolation rooms and associated design requirements including hand basin considerations, air changes per hour and HEPA filter requirements.
  • Inclusion of Positive Pressure Ventilated Lobby (PPVL) rooms as an additional isolation room type that may be provided in specialised circumstances.
  • Emphasis that combined alternating positive and negative pressure rooms are NOT recommended, however health services may decide at a local project level to optimise utilisation of Class N rooms by enabling them to switch between negative and neutral pressure modes.
  • Guidance on isolatable units or pods where provision of broader isolation capacity across a cluster/pod of beds or entire unit is required.
  • Updated advice to recommend that groups of Class N isolation rooms can be served from a common air handling unit.  However, this shall be informed by a risk assessment to ensure the operational impact, in the event of equipment failure, is acceptable.
  • Revised recommendations relating to the location of the exhaust grille in Class N and Q isolation rooms. This was previously recommended to be  located at a low level behind the bed head, however expert engineering advice, supported by Computational Fluid Dynamics (CFD) studies, recommends that the exhaust should be located on the ceiling above the patient, with the supply air diffuser located on the ceiling close to the wall at the foot of the bed.
  • Recommendation that anteroom doors should be interlocked to assist with containment (with an emergency break glass release for safety).
  • Revised guidance on monitoring room pressure, recommending that Class P, N and Q isolation rooms are equipped with a local audible and visual alarm and remote monitoring via a Building Management System (BMS).
  • Updated advice regarding strategies to minimise room air leaks and recommended approach to air pressure leak testing.

A thank you is extended to all those who have contributed to the review and update of this document.

Kind regards,

The AusHFG Team