Quality assurance
In order to comply with the highest demands with respect to the quality of our products, various standards are incorporated into our planning and production process.
DIA-Nielsen is certified to DIN EN ISO 9001:2000.
The plastic granulates used for our laboratory trials materials are obtained only from suppliers who guarantee that these comply with the strict regulations applicable to analysis and medical products. If necessary, we provide excerpts from the relevant certificates.
The same applies to the membranes from various well-known manufacturers which we fit into the filter units. These manufacturers also guarantee the quality of the products use by us by means of various certificates and a wide range of technical data.
We also carry out comprehensive in-house goods-receipt checks by our quality assurance department. Routine tests are applied with regard to various parameters, such as the bubble-point of the membranes, visual faults and the dimensions (thickness) of the raw membrane material, so that we can form our own picture of the condition of the goods received.
The high-quality membranes are stored under the controlled conditions of the clean-room at constant air humidity in special containers, and stamped out and further processed from the roll material immediately before final assembly, in order to ensure the most homogenous possible membrane surface.
The production of the filter units is carried out under controlled conditions (clean-room class ISO 7). The components of the filter units are produced directly in our clean-room, where the largely automated final assembly and imprinting is also carried out.
Clean-room classes to ISO 14644-1:
| Particles per m³ | ||||||
|---|---|---|---|---|---|---|
| Class | 0,1 µm | 0,2 µm | 0,3 µm | 0,5 µm | 1,0 µm | 5,0 µm |
| ISO 6 | 1.000.000 | 237.000 | 102.000 | 35.200 | 8.320 | 293 |
| ISO 7 | 352.000 | 83.200 | 2.930 | |||
| ISO 8 | 3.520.000 | 832.000 | 29.300 | |||
During assembly, the filters are checked several times for any visible faults by means of sensors and a camera monitoring system. Following assembly, these are followed by the usual tests to the AQL standard, which monitor the bubble-point and the burst pressure of the filters. This checks the integrity of the membranes and connection of the membranes to the filter housing, together with the quality of the weld connection or edge-injection.
