EN 1751

Air terminal devices (ATDs) are components of a ventilation system that control the flow of air into and out of a space. They include a wide range of devices, such as diffusers, grilles, registers, dampers, and valves.

Dampers and valves are ATDs that are used to open, close, or regulate the flow of air. Dampers are typically used in larger systems, such as those found in commercial and industrial buildings, while valves are more commonly used in residential and smaller commercial buildings.

Aerodynamic testing is used to measure the performance of dampers and valves in terms of their airflow resistance, leakage, and noise. This testing is important to ensure that the ATDs are meeting their design specifications and will perform as expected in the field.

The European Standard EN 1751 specifies methods for the aerodynamic testing of dampers and valves used in air distribution systems with pressure differences up to 2 000 Pa. The tests incorporated in this standard are:

• Leakage past a closed damper or valve
• Casing leakage
• Flow rate/pressure requirement

Leakage testing is used to measure the amount of air that leaks past a closed damper or valve. This is important to ensure that the ATD is providing a good seal and that it will not allow unwanted air to enter or escape from the space.

Casing leakage testing is used to measure the amount of air that leaks through the casing of a damper or valve. This is important to ensure that the ATD is well-constructed and will not leak air, even when it is under pressure.

Flow rate/pressure requirement testing is used to measure the amount of air that can flow through a damper or valve at a given pressure drop. This is important to ensure that the ATD is sized correctly for the application and will provide the required airflow.

Aerodynamic testing of dampers and valves is typically performed in a laboratory setting using a specialized test rig. The test rig simulates the conditions that the ATD will experience in the field and allows for accurate measurements of its performance.

The results of aerodynamic testing are used to classify dampers and valves according to their performance. This classification information can then be used to select the appropriate ATD for a particular application.

Benefits of aerodynamic testing of dampers and valves:

• Ensures that ATDs are meeting their design specifications
• Verifies that ATDs will perform as expected in the field
• Helps to select the appropriate ATD for a particular application
• Improves the energy efficiency of ventilation systems
• Reduces noise levels from ventilation systems
• Improves the indoor air quality of buildings

Overall, aerodynamic testing of dampers and valves is an important part of ensuring the proper performance of ventilation systems. By testing ATDs prior to installation, engineers and contractors can be confident that they are providing their clients with reliable and efficient systems.