Fire doors are an important part of any building's fire safety system but they only work effectively when closed. Door closers are devices that are fitted to fire doors in order to keep them closed or to trigger closing when necessary.
When a fire door is opened, the door closer automatically closes it again, helping to prevent the spread of fire. Door closers come in a variety of sizes and styles to suit different types of doors, and have 4 door closer control zones.
It is important to make sure that the door closer is suitable for the type of door it will be fitted to. You can read more about the types of door closers available in our blog here.
Back checks
The backcheck on a fire door is an important safety feature that works by stopping the door at a certain point when it’s opened. Once the door is opened the backcheck engages to slow down the opening speed of the door, to stop it smashing into anything or anyone behind it. This is the first control zone to be engaged and can be set to open the door to a certain angle. The backcheck should be checked regularly to make sure it is working properly.
Main Speed
The second control zone to be engaged is the main speed at which the door closes.This stage is often also referred to as the sweep. A spring inside the door closer can be adjusted to increase or decrease the closing speed. It is important to make sure that the door closes with enough speed to engage the latch nut not so fast that it risks damaging the door hardware. If you want to know more about how to adjust the sweep, you can find out more in our blog here.
Latch Speed
The next control zone to be engaged is known as the latch speed. When the door is about 6 inches away from being fully closed the door closer can increase the speed of the door to make sure it does not meet any resistance when latching to fully closed.
Delayed Action
Delayed action is an optional door closer control that is useful in areas of heavy traffic where many people are using the door regularly. The delayed action slows the initial closing speed of the door allowing more time for traffic to pass through.
Conclusion
Door closers have many features which allow them to be fully adjusted to suit the environment that they are being used in. Fire doors can only be relied upon to prevent the spread of fire and smoke when they are fully closed and latched so a door closer is an essential part of door hardware. It is important to understand and consider all of the control zones when fitting a door closer and adjust the zones where necessary.
For more information on how to install a fire door read our blog here. If you need any advice on finding the right fire safety equipment for your project then don’t hesitate to call our team 02920 857 959 or email [email protected].
