Letter: In brief

Sir: Your article "How to avoid a critical mess" (19 June) could be taken to imply that nuclear criticality issues at Dounreay are not properly considered.

Criticality is assessed entirely separately from other aspects of plant safety. Separate operations do not proceed unless they are within the limits set out by a criticality clearance certificate. These are independently assessed and reviewed by our own safety experts, by independent teams and by our regulators, the Nuclear Installations Inspectorate.

Dr ROY NELSON

Dounreay Director

UK Atomic Energy Authority

Dounreay,

Caithness