Which of the following are true regarding pulse oximetry? …

Which of the following are true regarding pulse oximetry?  Hazard includes pressure sores from prolonged application of the probe  Results may provide false-negative results for hypoxemia  Potential exists for burn and/or electrical shock from an incompatible probe  Works well in conditions where low perfusion exists 

Why are zone valves incorporated into a hospital’s central g…

Why are zone valves incorporated into a hospital’s central gas piping systems?   I. to terminate O2 delivery to an area in case of fire II. to allow selective maintenance of an area without shutting the system down III. to allow variable pressure reduction throughout the system