This part of IS0 11933 specifies the designation and characteristics of the various components for containment enclosures which are fixed to the containment enclosure wall or which can be used in conjunction with the lead shielding units described in IS0 7212 and IS0 9404 and used in the construction of containment enclosures for protection against ionizing radiation. These components may also be used alone, without any shielded enclosure. In addition, some similar units are included which can be used with or without shielding, but not in conjunction with units given in IS0 7212 and IS0 9404. The units covered by this part of IS0 11933 are: - glove/bag ports, - bungs for glove/bag ports, - enclosure rings, - interchangeable units which are either leaktight ejectable units (support rings for gloves, welded bags, gaiters for remote-handling tongs and for manipulators, circular windows) or rigid plugs or securing units (securing rings), Independent systems which do not use the same support ring are described separately in this part of IS0 11933 (support rings for manipulator and tong gaiters and for circular windows and rigid plugs). The associated leaktight components (gloves, welded bags, gaiters for remote-handling tongs and for manipulators) are described in IS0 11933-2. Transfer systems (plain doors, double doors, airlock chambers, leaktight connections for waste drums) are dealt with in IS0 11933-3. Accessories for the ventilation of containment enclosures such as filters and traps, pressure regulators and safety valves, are dealt with in IS0 11933-4. Penetrations for electrical and fluid circuits will be described in IS0 11933-5. The elements constituting the framework of containment enclosures (metallic walls, framework, transparent panels) are dealt with in IS0 10648-l.