point many such information is stored and then evaluated to give an overall image. This takes time. Directly imaging procedures are faster: Microwave versions are either electronic or make use of planar microwave detector consisting of a microwave absorbing foil and an infrared camera (NIDIT procedure). Applications Microwave testing is a useful NDT method for dielectric materials. Among them are plastics, glass-fiber reinforced plastics (GFRP), plastic foams, wood, wood-plastic composites (WPC), and most types of ceramics. Defects interior in the DUT and at its surface can be detected, e. g. in semi-finished products or pipes. Special applications of microwave testing are non-destructive moisture measurements wall thickness measurements measurements of paint thickness on carbon composites (CFRP) condition monitoring, e. g. presence of gaskets in assembled valves, rubber based piping in heat exchangers measurement of material parameters, e.g. permittivity and residual stress disbond detection in strengthened concrete bridge members retrofitted with carbon fiber reinforced (CFRP) composite laminates corrosion and precursor pitting detection in painted aluminum and steel substrates flaw detection in spray-on foam insulation and the acreage heat tiles of the Space Shuttle. Microwave testing is used in many industrial sectors: aerospace, e. g. non-destructive paint thickness measurements on CFRP automobile, e. g. NDT of organo sheet components and of GFRP leaf springs civil engineering, e. g. radar applications energy supply, e. g. test of rotor blades of wind power plants, riser pipe security, e. g. body scanner on airports In the last years the need for NDT has increased generally and especially also for dielectric materials. For this reason and because microwave technics more and more are used in consumer products and hereby became much less expensive, NDT with microwaves increases. In recognizing this growing importance, in 2011 the Expert committee for microwave and THz procedures of the German Society of Non-Destructive Testing (DGZfP) was founded as in 2014 the Microwave Testing Committee of the American Society for Non-Destructive Testing (ASNT). Standardization work is at the beginning. References Literature Joseph T. Case, Shant Kenderian: MWNDT – An Inspection Method. In: Materials Evaluation, March 2017, 339-346. (This paper contains many links regarding microwave testing) Reza Zoughi: Microwave Non-Destructive Testing and Evaluation Kluwer Academic Publishers, Dordrecht 2000. N. Ida: Microwave NDT Springer Science & Business Media, Luxembourg, 2012 External links [1] Microwave-Testing: An-Overview [2] Non-destructive Testing of WPC Planks using the Non-Ionizing Direct Imaging NIDIT procedure [3] Electronic Microwave Imaging with Planar Multistatic