Microwave safety aspects

It should be obvious from a scientific standpoint that the question of microwave effects needs to be addressed in a serious manner, given the rapid increase in the use of microwave technology in chemical sciences, in particular organic synthesis. There is an urgent need to remove the black box stigma of microwave chemistry and to provide a scientific rationalization for the observed effects. This is even more important if one considers safety aspects once this technology moves from small-scale laboratory work to pilot- or production-scale instrumentation. 

Kappe, O. Stadler, A. Limitations and Safety Aspects. In Microwaves in Organic and Medicinal Chemistry WUey-VCH Weinheim, 2005 Section 5.4 pp 103-105. 

MAOS is considered a part of green chemistry as it provides solid support and/ or solvent-free reactions (Varma, 1999). The growth of this technology and its use in organic reactions is slow as compared to combinatorial chemistry and computational chemistry. This is all because of the fact that the fundamentals of microwave dielectric heating were not very clear at that moment. This is further supported by lack of reproducibility and controllability as well as its unsafe nature. With the development of the solvent-free reactions, the safety aspects were improved making... 

Microwave-assisted sample digestion has its own safety requirements. As a result of the direct energy absorption and rapid heating, microwave techniques introduce unique safety considerations that are not encountered in other methods. Differences in conditions between traditional laboratory practices and microwave-implemented methods should be examined before microwave energy is used to heat reagents or samples. An excellent suimnary of this aspects is given in the literature [18, 19, 175]. 

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