Abstract: A flexible, submersible compartment for underwater work in dry conditions which is particularly suited for work on petroleum drilling structures. The flexible, submersible compartment includes a flexible bell of reinforced elastomeric material having an opening surrounded by a collar at its top portion. A rigid platform-brace having a contractible outer ring is located beneath and attached to the flexible bell. The platform-brace also includes an inner ring which can be secured to a submerged portion of the petroleum drilling structure. In the event of contact with a rigid obstacle, the flexible bell adapts to the shape of the obstacle while the platform-brace contracts.