An AOV system (Automatic Opening Vent system) is a type of smoke ventilation system designed to remove smoke and heat from a building during a fire.
Rather than being a single product, most AOV systems consist of multiple components working together to detect smoke, open vents automatically, and help keep escape routes clearer for occupants and emergency services.
You’ll commonly find AOV systems installed in apartment buildings, residential developments, commercial properties, and other buildings where smoke control forms part of the overall fire strategy.
Their primary role is simple: to help control how smoke moves through a building during a fire and support safer evacuation.
How does an AOV system work?
AOV systems are designed to activate automatically when a fire is detected.
In most systems:
- A smoke detector/fire alarm is activated
- The control panel receives the signal
- The relevant AOV opens automatically
- Smoke rises through the vent out of the building
Depending on the building design, smoke may be vented directly outside through an AOV window, roof vent, skylight, or louvre. In larger buildings, smoke may be directed through a smoke shaft using smoke control dampers.
Most AOV systems also include battery backup and manual override controls to ensure the system remains operational during an emergency.
What Components Make Up an AOV System?
| Component | Purpose |
|---|---|
| AOVs (Vents) | Windows, roof vents, skylights, louvres or dampers that open to release smoke. |
| Smoke Vent Control Panel | The central unit that recives signals and controls operation of the AOVs |
| Smoke Detectors / Fire Alarm Interface | Triggers the system when smoke is detected |
| Manual Override Controls | Allow firefighters to manually operate the system if required. |
| Smoke Control Dampers | Open within smoke shafts to direct smoke from corridors and lobbies into the shaft. |
Types of AOV Systems
Natural AOV Systems
Natural AOV systems use the natural movement of hot smoke rising through the building. Once activated, AOV vents open to allow smoke and heat to escape naturally.
These systems are commonly used in:
- Stairwells
- Corridors
- Smoke shafts
- Residential buildings
Mechanical AOV Systems
Mechanical systems use powered extract fans to remove smoke from the building.
These are typically used where natural ventilation alone may not be sufficient, such as:
- Larger buildings
- Complex layouts
- Buildings over 30m
- Basement or internal areas without natural ventilation
Mechanical systems are generally more complex and often require additional fire engineering and airflow calculations.
Regulations and Standards for AOV Systems
Because AOV systems are life safety systems, they must be designed and installed in line with relevant smoke ventilation regulations and standards.
Common guidance includes:
Together, these standards help define how the smoke ventilation system should perform, how products should be tested, and what level of smoke control may be required within the building.
Getting an AOV system right is about more than just products, it’s how everything works together.
At Rocburn we help review drawings and fire strategies to ensure systems are correctly specified and compliant.
Learn more about the AOV systems and kits we scan supply.
Related Posts
The Impact of Poor Workplace VentilationWorkplace ventilation has a bigger impact than many people realise. While it’s often overlooked, poor ventilation in the workplace can affect everything from employee comfort and wellbeing to concentration, productivity, and sickness levels. When fresh air isn’t able to circulate properly, pollutants, moisture, and CO₂ can build up indoors. Over time, this creates an uncomfortable working environment that can leave employees feeling tired, distracted, and less productive. The effects of poor workplace ventilation aren’t always obvious straight away, but they can have a significant impact on both staff and business performance. What Happens When Ventilation is Poor? Every workplace generates [...]
What is Natural Ventilation?Natural ventilation is the process of supplying and removing air from a building using natural forces, rather than mechanical systems like fans or ductwork. Instead of relying on powered systems, it uses airflow created by wind and temperature differences to move fresh air in and stale air out. This makes it one of the most simple and effective ways to improve indoor air quality in many buildings. How Does Natural Ventilation Work? Natural ventilation works by creating airflow through openings, there are three main ways this happens: Cross ventilation (wind driven) Cross ventilation happens when air moves from one side [...]
Single-zone vs Multi-zone Smoke VentilationSmoke ventilation systems are designed to keep escape routes clear during a fire by removing smoke and heat from the building. One of the first things to understand when looking at smoke ventilation is whether your project requires a single-zone or multi-zone system. This will depend on building layout, the number or areas (zones) that need to be protected and how the system is expected to operate in a fire. What is a Single-zone Smoke Ventilation System? A single-zone system protects one are only, such as a stairwell, corridor, or lobby. In this type of system, everything operates together. When [...]
Smoke Control Systems