Stairwell Pressurisation

The Building Code of Australia in Part E2 Smoke Hazard Management in clause E2.2 General requirements stipulates compliance with Table E2.2a General Provisions which requires any fire-isolated stairway to be provided with stairwell pressurisation – an automatic air pressurisation system. The BCA requires a stairwell pressurisation system to ensure the occupants of a building in a fire emergency have sufficient time to evacuate the building before the stairwell becomes untenable. A stairwell pressurisation system will be nominated by the building surveyor/ building certifier in the essential safety measures determination/ schedule.

Building Code of Australia

A stairwell pressurisation system must be installed in accordance with AS/NZS 1668.1:1998 The use of ventilation and air-conditioning in buildings – Fire and smoke control in multi-compartment buildings and the building permit. When installed, the stairwell pressurisation system will be in Normal Mode and Fire Mode (if needed). In the event of a fire detection system detecting a fire in the buildings, the stairwell pressurisation system will automatically change to fire mode and start the system.

The following illustration depicts stairwell pressurisation relief in Class 2 or 3 buildings.

The following part extract of clause I1.1 Safety Measures (as appeared in BCA 2013) covers stairwell pressurisation:

Table I1.6 Safety Measures – Air Handling Systems

Safety Measures BCA Provision for Determining Standard of Performance
Smoke hazard management systems – Automatic air pressurisation systems for fire-isolated exits (stairwell pressurisation). E2.2

Essential Safety Measures Audit – Stairwell Pressurisation

An essential safety measures auditor must be aware that stairwell pressurisation systems maintenance is to comply with AS 1851-2005 Maintenance of fire protection systems and equipment, Section 3. The essential safety measures auditor should check the stairwell pressurisation contractors logbook required under AS 1851-2005 for any deficiencies in inspection, testing or maintenance in the building’s essential safety measures logbook to ensure fire safety compliance when signing the Annual Statement, Annual Certificate Compliance, Annual Fire Safety Statement, Annual Maintenance Statement and Annual Occupiers Statement.