Filter vent fitting

摘要

A filter vent fitting for a drum which allows for the passage of hydrogen gas but precludes the passage of radioactive particulates, the fitting having evacuation/pressurization conduits which allow the drum to be evacuated or pressurized, and cryogenic/sapling conduits which allow the temperature of the drum to be reduced and samples drawn from the interior which are not filtered. Preferably a cap member is provided with a pressure balancing bore which is active during the evacuation and pressurization steps.