c. Obtain Equipment. Obtain the following equipment as needed.
(1) Full oxygen tank (cylinder). Oxygen tanks are usually kept in a central
location designated by the hospital SOP.
(a) Oxygen tanks are color coded (painted) green; however, the
international color code for oxygen is white.
(b) Tanks are available in various sizes, but the most commonly used
tanks are D, E, and M cylinders. The "D" tank contains 356 liters of oxygen; the "E"
contains 650 liters; and the "M" contains 3,000 liters. Each is filled to specified limits
with a pressure of from 2,000 to 2,200 pounds per square inch (p.s.i.). As the oxygen is
used, the pressure decreases. A tank is considered to be sufficiently pressurized for
use as long as it maintains a pressure of 500 p.s.i. or greater.
(c) Check the tag on the oxygen cylinder. The oxygen cylinder tag is a
three-part perforated design with the three sections labeled "Full," "In Use," and "Empty"
(figure 3-3). The tag should have all three sections intact. When the cylinder is turned
on for use by the patient, the "Full" segment is torn off. When the tank is empty, the "In
Use" segment is removed, leaving the only the "Empty" portion of the tag. The tank is
considered to be empty when the gauge reads 500 p.s.i. A residual pressure of 200
p.s.i. should be maintained on all tanks.
Figure 3-3. Cylinder tag.