Abstract: A safety enclosure providing quick and easy access to the processing area comprising a counter-weighted movable open ended cylinder capable of being raised and lowered and in this lowered position can be securely affixed by swing away clamps to a flanged pressure vessel head containing processing equipment for pyrotechnic materials whereby detonation of materials in the enclosure during processing contains and directs the blast upward through the blast venting protecting the workers and equipment external to said safety enclosure.