Abstract: A controlled environment system and method for constructing same provides for the containment and safe handling of toxic waste materials which are ultimately collected and disposed of without contamination of the external atmosphere. The system generally comprises a frame, a seamless tube-like liner connected to the interior of the frame, at least one air lock disposed within the liner for compartmentalizing the liner, and a negative pressure source for creating a negative-pressure environment within the liner so as to prevent the escape of toxic waste materials therefrom. The invention also includes a unique retainer ring for interconnecting adjacent structural members during assembly, and for rapidly disconnecting the structural members during disassembly without the use of a tool.