The bunker itself was circular in shape with a domed ceiling. Contoured seats, large enough for a fully suited astronaut, ringed the perimeter of the room. Also inside the room were fire blankets, and supplies to sustain the occupants for 24 hours. Charts on the wall gave guidance to the occupants as to when to light oxygen candles to replenish breathable oxygen, and when to change the CO2 scrubbers to remove excess carbon dioxide from the air. A radio link was available for communication with rescuers and responders. A toilet was installed behind one of the seats.