UDF Modules

UDF Module
Do you need protection against contamination from the surroundings? 
A UDF module might help you....

How does it work?
The UDF module is a highly developed unit used to protect the material to be handled inside the working area. The unidirectional airflow in the working area protects the material against contamination from the surroundings.  

Our UDF modules are constructed in accordance with the following standards: 
  • Recommended Practice:IES RP-002-86; January 1986; Laminar Flow Clean Air Devices
  • Den nordiske R3-Forenings Norm för öppna LAF-enheter
  • ISO 14644-4: Design, construction and start-up
  • ISO 14644-7: Separate enclosures 
The UDF module is constructed to offer protection of the working area against particles and other contaminants that could harm the “product” handled in the unit. The working area is defined as the area below the downflow filter surface of the UDF module. All modules have been thoroughly tested prior to leaving the factory in accordance with: 
  • IES RP-CC006.2
  • ISO 14644-2: Specification for testing and monitoring with a view to continued conformity with ISO 14644-1
Applications and options 
The module is constructed and assembled in a way that all joints are discretely hidden and no sharp edges and open holes can be found. This enables easy cleaning.  

Operation of the UDF module is done via a soft touch control panel (full speed, full light,  emergency stop, visual downflow alarm), which is mounted on the left front leg of the unit. An audible alarm is mounted on the PCB. 2 fluorescent light tubes, placed discretely between the laminator and the main filters, ensure good lighting conditions in the working area and a minimum of disturbance of the unidirectional downflow. 
Air is led into the UDF module through G3 prefilters located at the front of the module. From the prefilters the air is sucked, by the ventilators, into the plenum, where a guide plate distributes the air to ensure very little variation in the local downflow air velocity in the UDF module. The air is lead through the H14 main downflow HEPA filters and the laminator before entering the working area. The laminator makes it possible to achieve a very uniform laminar airflow inside the working area of the UDF module. The airflow passes through the working area underneath the unit, in a vertical downflow with an average nominal velocity of 0,45 m/s, with all measured single values within ± 20 % of the average air velocity.  

Just below the laminator a flow sensor is located. The flow sensor measures the downflow air velocity and regulates the speed of the ventilators to get a constant air velocity in the downflow. With the gradual build-up of particles in the main HEPA filters the flow sensor will detect a lower air velocity. Through the control system the speed of the ventilators is increased to compensate. This feature will give the main HEPA filters a longer life.  

On the front of the module a DOP outlet is placed. This is used during leak test of the downflow HEPA filters for determining the upstream aerosol concentration.  
A & H Medical    Knudslundvej 33 · DK-2605 Brøndby     Tel: +45 39 29 63 33        E-mail: