AOV Systems from Colt

What are AOV (Automatic Opening Vent) systems?

When referring to smoke ventilation systems in buildings, AOVs are smoke vents that will open and close automatically when triggered by a central control panel. They are typically activated by smoke detectors, either directly or from a smoke detection system - they open in the event of smoke being detected.

How do Automatic Opening Vents Work?

When the AOVs are activated and opened by the smoke ventilation control system, they allow smoke which may otherwise have started gathering in various parts of a building to escape to the outside of the building. This has obvious benefits for anyone still in the building, as effective smoke ventilation not only improves visibility but also reduces the levels of harmful toxic smoke, gases and toxins and increases their chances of a safe escape dramatically. As well as minimising smoke inhalation and helping people get safely out of the building, the automatic opening vents also assist fire fighters with getting into the building and to the seat of the fire quickly. Not only do they have cleaner air to breathe, visibility is also drastically improved. As firefighters will almost always be entering an unknown building, having the ability to see clearly will help them plan and move through the building much more quickly. As AOV smoke vents play such an important role in keeping people safe, they are typically roof mounted and installed in areas that protect stairwells, lobbies, corridors or other common escape and access routes.

Types of Automatic Opening Vent

Automatic opening smoke vents can come in the form of glazed or insulated casement, louvred or ‘flap’ ventilators with controls taking the form of:

  • A spring to open magnetic release (with manual reset)
  • Electric actuators or
  • Pneumatic controls and could look similar to the images below.

When do you need automatic opening vents in your building?

There are building regulations governing what types of buildings require smoke ventilation. As AOVs form an integral part of almost all smoke ventilation systems, building types that are outlined in these regulations will likely be required to install AOVs.

The most common types of buildings that could need smoke ventilation systems designed and installed are:

  • Large single storey buildings, such as factories and warehouses
  • Shopping centres
  • Multi-storey Residential buildings
  • Other multi-storey buildings with a fire fighting shaft, generally over 18m tall
  • Buildings with atria
  • Car parks where smoke, and fume extraction is required

Inevitably, due to differences in building layouts, heights, location etc. specialist advice should be sought to determine the exact requirements. However, for multi-storey residential buildings in England, the below image offers a simple overview of how an increase in height impacts on smoke ventilation requirements. Similar, but not identical requirements exist in Wales, Scotland and Northern Ireland.

Fire Safety Standards and Building Regulations

More information and guidance on how to design smoke ventilation systems in England and the regulations surrounding them can also be found in the resources below:

  • The Building Regulations 2000
  • Approved Document B
  • Codes of practice: BS 9999, BS 9991
  • Specifications: EN 12101 Parts 1, 2, 3, 6, 7, 8 & 10
  • Design Guidance: BR 368 – Design Methodologies for Smoke and Heat Exhaust Ventilation
  • BS 7346- 4, 5 & 7, CEN TR 12101-5
  • BS 7974
  • Smoke Control Association Guides

Colt Automatic Opening Vents

Colt has a range of AOVs to suit different types of project needs:

Each of these have their own different features and benefits eg. thermal insulation, air leakage, aesthetic appearance, mounting angle and space consumption that may suit one building more than another.

If you are working on a project that has AOV or other smoke ventilation needs, Colt’s experience and expertise can help you navigate the regulations to ensure you are installing the best system for your building’s requirements. Talk to our technical team for a free consultation today.