OHD Quantifit2, Руководство пользователя

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Chapter 20 | Troubleshooting | Graph Behavior
20
Troubleshooting
Traceline way above challenge pressure line
The QuantiFit2 traceline goes opposite of the direction of the pressure. If the line is above the
challenge pressure line, that means that there is too much negative pressure. In this case, a test
subject is most likely sucking in a breath during the test. If the line is below the challenge
pressure, that means that the QuantiFit2 couldn’t create enough negative pressure because the
leak is so great.
1. Movement by the person being tested needs to be minimized. Actions such as swallowing,
opening the mouth, and moving the tongue can adversely affect the pressure sensor and
will be indicated by an erratic traceline.
2. Air inhalation or exhalation, even slightly, creates dramatic changes within the respirator.
Re-instruct the test subject to maintain breath holding during the test measurement.
3. A test subject may be unable to stop the flow of air through the nose while holding his or
her breath. A nose clip can assist the subject (be sure that the nose clip does not interfere
with the fit of the respirator).
4. Improper breath hold. Instruct the user to relax, take a comfortable breath and hold as if
going under water.
The in-respirator pressure drops during the test
This graph would indicate that the challenge pressure was achieved, but during the test, a leak
source opened. This could be the result of a exhalation valve that is in poor condition, or from
the test subject moving his or her head and creating a leak in the seal.
1. Clean the exhalation valve
2. Replace exhalation valve
3. Examine the condition of the respirator