§ Mr. Robin F. Cook
asked the Secretary of State for Transport what is the recommended pressure within flasks used for the shipment of irradiated fuel; if the level has been exceeded since January 1975 in any flasks received at Barrow-in-Furness for transhipment to Windscale; and if any flask has been vented to release pressure within British waters or territory.
§ Mr. Horam
The maximum acceptable operating pressure within irradiated fuel flasks varies according to the type of flask, but will be between 3 and 4 atmospheres guage. Those arriving at Barrow are transported on long journeys and, because of gradual pressure build up, need to be vented periodically during the voyage and immediately before entry to any port. The discharged gas contains only slight amounts of radioactivity and venting is accomplished through a filter system under conditions approved by my Department to ensure no hazard to the ships crew or the public. On no occasion has the maximum operating pressure been exceeded, and on one occasion only have flasks been vented when delayed in port.