Procurement of Safe Viewports for Hyperbaric Chambers

Lack of ASME Pressure Vessel Code Standards for the selection of material, designs, fabrication techniques, and prooftesting methods for viewports in hyperbaric chambers makes it mandatory that engineering judgment be exercised to the fullest in the procurement of such viewports. Based on the experience gained by the authors in past experimental programs dealing with design criteria, and procurement of acrylic viewports for major Navy hyperbaric chamber installations, practical guidelines are proposed for specifying such viewports. The guidelines contained in this paper address themselves to selection of viewport shape, safety factor, material, fabrication, quality control, proof-testing, and periodic inspection.