[en] The accident at the Trawsfynydd nuclear power station in February 1986 is explained and the implications examined. In this article the leak of coolant carbon dioxide is considered as a LOCA and hence, the author suggests, should not be regarded as 'a minor incident' as described to the House of Commons. The author suggests that as the reactor has passed its design life span it is outdated, unsafe and more accidents are likely. (U.K.)