OXYGEN ANALYZER

The oxygen analyzer is used to verify the percentage of oxygen within a space. Several models, manufactured by different companies, are used throughout the Navy. One model commonly used in the Navy is the BioMarine Model OA225R (fig. 6-33) which is described below.

The Navy's Bureau of Medicine requires a space to have an atmosphere oxygen content of 20% before personnel can enter the space without an OBA or an air-line mask. The normal oxygen percentage level at sea level is 20.8%.

The BioMarine oxygen analyzer provides a continuous reading of the oxygen content concentration from 0070 to 25070 oxygen in any environment. An oxygen level below 20% or above 22% should be considered as a potentially dangerous situation. If the oxygen content is less than 20% the space should be ventilated and then retested.

The BioMarine oxygen analyzer requires oxygen to operate. Batteries are not required to operate this instrument. Once the sensor package is opened, the sensor's life is about 1 year if the rubber plug is reinstalled after each use.

Figure 6-33.-BioMarine Oxygen Indicator Model OA225R

The oxygen analyzer should be calibrated before each use. To calibrate the instrument, expose the sensor to fresh air on the weather deck. A calibration screw is located below and to the left of the meter. Use a screwdriver and rotate the calibration screw clockwise until the meter reads more than 22%. Then turn the calibrating screw counterclockwise until the meter reads 21%. If the meter can not be adjusted to read more than 22%, the sensor is getting near the end of its operating life and must be replaced. Do not throw the instrument away. You can order replacement sensors through your normal supply channels.

To operate the oxygen analyzer, use the following procedures:

1. Insert the remote sensor cord connector in the top of the metal meter case. Turn the connector clockwise three-fourths of a turn to lock it in place.

2. Remove the rubber discard plug from the sensor face. Do not throw the rubber discard plug away; you will need to replace it later.

3. Calibrate the oxygen analyzer as described above.

4. Send the sensor into the space to be tested and check all around the compartment. The person inside the space with the sensor must wear an OBA or an air-line mask. Observe the meter constantly while conducting the test. Make a note of the lowest reading you get.

5. Upon completion of your tests, flush the instrument with fresh air.

6. Reinstall the rubber discard plug on the sensor.

7. Disconnect the remote sensor cord from the metal meter case.

8. Store the oxygen analyzer in a clean, dry area.