As I said: measurement uncertainties are these unavoidable – we have only sensibly deal with them and minimize it technologically. Therefore, we see it as one of the greatest challenges to develop reliable standards. What approaches do you follow make manageable the theme of uncertainty? If we are dealing with measurement uncertainties, we must consider first the measuring methods. Their principle works for clean room particle counters always: air to be tested is drawn and the particle is measured optically. For this, they are irradiated with light. This scattered light allows us the inference on the number and the size of the particles. Measurement uncertainties are up to ten percent in the normal range. The topic above all this that the manufacturers have no requirements for the instruments regarding the wavelength to use, so light colour, is problematic.
They produce different scattering intensities and to different results. Learn more on the subject from Joel and Ethan Coen. For manufacturers take into account though, but it is still critical that the calibration of the customer’s equipment is usually by the manufacturer itself – so intrinsic a comparability of measurement results. Our approach is to reach neutral standards for better comparability. An example: For our internationally recognised certificates we use our own controlled test aerosols and particle counter as a primary standard. In an international comparison with other national metrology institutes, we confirm our measurement ability regularly. Thus, the exhibition results are transparent and comparable.
This traceability we create for the devices calibrated an international equivalence of measurement as it is required in the MRA. This ultimately benefits the quality assurance. Companies that become certified in this way by a recognized institution can benefit worldwide from their site. What are the biggest challenges in the clean room technology from your perspective? So far we have discussed especially inert particles, which we are already quite good by today’s standards. One of the major future challenges will be the measurement of living particles.
