Preface Adhesion is a phenomenon architects and civil engineers are not very familiar with. In other disciplines knowledge about surface properties and the background of bonding energies is also far from satisfactory; nevertheless there are many important· applications in concrete engineering, where adhesion is necessary for success and durability. These include: - coating and painting - repair of concrete surfaces - bonding of fresh to old concrete - crack injection - glueing of precast elements - glueing of steel to concrete, etc. In 1981 RILEM established the technical committee 52-RAC 'Resin Adherence to Concrete'. The main aims of the committee's work were - to collect research results and practical experiences - to initiate and coordinate research programs - to develop, on a scientific base, test methods for field and for laboratory purposes. One of the results of the committee's work is a state-of-the-art report, which will be presented orally as a General Report at the International Symposium ISAP '86, and will be printed either in the RILEM journal Materials and Structures or separately. Several test recommendations have been elaborated and will be prepared as drafts for the participants ofISAP '86. These are: - direct tensile test - pull-off test - direct shear test - slant shear test - four-point bending test - dynamic loading test - thermal compatibility test (two versions) - injectibility test.

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Whenever radioactivity is released to the atmosphere, for example by the detonation of nuclear weapons or the testing of nuclear weapons or from nuclear reactor accidents that fraction of it which remains airborne for more than a few hours is liable to be attached to aerosol particles. The resulting radioactive aerosols are carried by atmospheric mixing processes until they settle out or are scavenged by precipitation. The radiation exposure pathway of maximum concern to humans is by inhalation of aerosols and their deposition in the respiratory tract. In this context, it is important to note that radioactive aerosols are commonly of natural origin alos. In particular, the associated radionuclides can be of natural terrestrial origin, such as the decay products of radon gas, or they can e cosmogenic, such as beryllium-7. The exposure of miners of uranium and other ores and minerals to radon and its aerosol-borne decay products is of major significance. The book describes the formation of aerosols, their aerodynamic size distribution, their atmospheric residence time, their sampling and measurement, the range of radioactive aerosols found and studied thus far, including man-made nuclides and radon decay products and their interaction with man, including deposition in the lung and subsequent health effects. - Advanced level science handbook for researchers, scientists and academics - Covers all aspects of radiation exposure in humans, including subsequent health implications - Presents the latest findings and analysis in this highly topical area