A. Wall to inlet

1. Diameter-indexed safety system (DISS)-couples oxygen and nitrous to wall
2. Colored tubing
3. Pin-index safety system-couples cylinders to machine
4. Colored cylinders

B. The machine

1. Fluted (Calverly) control handle on oxygen rotameter
2. Oxygen located on far right side of the manifold
3. Stopper located on top of flowmeters so that the indicator ball/bobbin won't plug the manifold
4. Fail-safe machanism that alarms if oxygen pressure is below 25 lbs/sq. inch (note: does not guarantee oxygen flow, only oxygen pressure)
5. Oxygen ratio monitor controller to link N2O flow to oxygen flow

C. The ventilator

1. Disconnect alarm indicating low pressure
2. Alarms for subatmospheric, continuing and high pressure
3. Oxygen powering the bellows so that a hole in the bellows will let pure oxygen enter

D. The breathing circuit

1. Oxygen analyzer. Mandatory equipment--there is no way of knowing that you are delivering oxygen unless there is an oxygen analyzer