General radiation problems for insulating materials in future fusion devices

It is envisaged that ITER will come into operation early in the next centur y. This next step machine will present problem due to the radiation damage effects in the numerous insulator components. The effects on the electrical conductivity, optical and mechanical properties are discussed in the light of recent advances and results. Material successes for the ECRH windows ar e presented, together with reasons for concern in the NBI system due to enh anced gas conductivity. (C) 1998 Elsevier Science B.V. All rights reserved.