Fiber optic cables are the backbone of modern data transmission technology and require the highest precision in production and testing. Diamond SA carries out part of its production in clean rooms and has now put two new clean room facilities into operation.

A special feature of the new cleanrooms is the dark inspection, which makes it possible to use UV light to detect residual contamination on components that remain invisible in normal light. This inspection is crucial to ensure that the strict cleaning requirements are met.

Customized cleanroom solution with dark room

The tailor-made cleanroom solution from Schilling Engineering integrates a separate, 15-metre-long UV area into the cleanroom system. The innovative black coating of the room, including the dove-blue floor, minimizes reflections and creates ideal conditions for UV-supported dark testing. The composite panels used have the same coating thickness as the usual white panels, which ensures the same chemical resistance and cleanability.

Access to the new cleanrooms is via an opaque, black-painted swing or sliding door, which is not only functional but also aesthetically pleasing. In order to keep the amount of light entering the dark room as low as possible, a special air duct was planned for the air conditioning in the ceiling plenum and a special overflow. To achieve this, the overflow grilles were not installed directly in the wall as usual, but were offset so that the air is drawn in at the bottom and blown out at the top. 

Complete darkening for effective UV light testing

Thanks to the option of completely darkening the room and creating no light gap, UV light testing can be carried out very effectively using flashlights or permanently installed lamps. Residual particles fluoresce under the UV light and can be detected faster and better thanks to the strong contrast of the black walls and table surfaces.

There are two light scanners in the dark room that can be used to switch off the ceiling lighting at the workstation. During the test, this is signaled outside the room by a traffic light so that the test is not interrupted. The cleanroom area with darkroom therefore not only enables effective cleaning and testing of the products, but can also be used as a regular cleanroom area.

Outgassing-free sealants

Special requirements also applied to the sealing materials used in the cleanroom systems. Sealants can release outgassing that could damage the high-precision products. For the project in Losone, the cleanroom company was therefore given a choice of special outgassing-free sealants.  The new materials initially presented the service technicians at Schilling Engineering with challenges, as they were more difficult to process than the standard sealants, but were able to be used well as experience grew.

With the successful commissioning of the state-of-the-art facility, Diamond SA impressively demonstrates how specialized environments can raise product quality to a new level. The customized cleanroom solutions are an important building block for the technological progress of its customers.