Electromagnetic moisture measurement technologies have proven to be valuable tools in diverse applications. This monograph covers basic aspects of nondestructive electromagnetic methods of water content determination and relates to the associated highly multidisciplinary field of research and development. It also presents a comprehensive selection of relevant field-tested methods and instruments. The fundamentals of electromagnetic field interactions with dipolar materials are briefly discussed, with special attention towards the dielectric properties of water and aqueous solutions. A tutorial and overview of electromagnetic measurement methods is presented, including dielectric spectroscopy in broad frequency and time domains, as well as dielectric imaging techniques. This review is complemented by a demonstration of successful real-world implementations for the moisture determination of soils, snow, buildings and building materials, food and agricultural goods, as well as various industrial products. The text is completed by a guide concerning the use of reference liquids for the calibration of sensors and instrumentation and by a bibliography of more than 850 references. The monograph is useful as a reference book for researchers and engineers and as a textbook for upper-level students interested in the water content determination of materials.

Mformation about a material can be gathered from its interaction with electromagnetic waves. The information may be stored in the amplitude, the phase, the polarisation, the angular distribution of energy transportation or the spectral characteristics. When re trieved from the wave, certain material properties may thus be determined indirectly. Compared on the one hand to direct material analysis, an indirect method requires calibration and is prone to interference from undesired sources. On the other hand, however, it permits the determination of features inaccessible by direct methods, such as non-destructive material interrogation, high measurement speed, or deep penetration depth. However, being a physical method, the use of electromagnetic waves is still handicapped by the lack of acceptance by many chemists, who are used to applying direct approaches. Historically, the first application of electromagnetic wave interaction with mat ter involved measurement of amplitude changes at a single frequency caused by material properties, and it is still used today by some systems. This approach was soon supplemented by single frequency phase measurements, in order to avoid distortions through amplitude instabilities or parasitic reflections. Such single pa rameter measurements of course require dependence only on one variable in the measured process and sufficient stability of all other ancillary conditions. If that is not the case, the single parameter measurement fails.

The first book to address all theoretical and practical aspects of electromagnetic wave interaction with water and moist materials, this unique book features 29 full-length, peer-reviewed papers prepared by 69 of the world's experts in aquametry for a key Workshop held in conjunction with the IEEE MTT-S International Microwave Symposium in Atlanta, Georgia, 1993. Collectively, the papers illustrate the physical background of microwave techniques used for moisture content determination, present stimulating examples of applications of microwaves for nondestructive and accurate measurements, and demonstrate successful implementation of techniques in a variety of industries.

RILEM TC 248-MMB was established in 2012 with the main aim to improve and distribute knowledge related to moisture measurement in construction materials in various scientific and industrial applications. Properties and performance of building materials and structures are influenced to a large extent by the moisture conditions in the materials. Obvious examples are heat conductivity, shrinkage and creep, transport properties, most types of deterioration, discoloration etc. For research and applications the moisture conditions must be quantified, by measurements in the laboratory or under field conditions. There is much variation in methods being used, even within the same topic, in different countries, both with regard to materials and to applications. No consensus whatsoever does exist. For the construction industry it is important to be able to quantify the moisture conditions in an accurate way in various applications. This state-of-the-art report is divided into two parts, Principles and Applications, with altogether 28 chapters on various moisture measuring principles and a number of applications.