Testing Scba With Positive-Pressure Mask And Lung Demand Valve - Dräger Testor 2500 Notice D'utilisation

4.4.6 Testing SCBA with positive-pressure mask and
lung demand valve
Visual inspection
Inspect all components. Check in particular for possible

damage (e.g. deformation, adhesion, contamination or
cracks). Replace faulty or damaged parts immediately.
Preparation of test
1. Connect pressure reducer to the inlet for the compressed
air supply.
2. Moisten the sealing surface and exhalation valve with water,
if necessary.
3. Mount the full face mask on the test head.
4. Connect the lung demand valve to the full face mask.
5. Seal the hose of the lung demand valve.
WARNING
The following work is on the high-pressure system. If parts
become disconnected from the system, there is risk of injury.
► Make sure that all connections are secure before opening
the cylinder valve.
6. Open cylinder valve.
Test for leaks
1. Press left control lever to generate a negative pressure of
approx. -15 mbar.
2. Pull left control lever to generate a negative pressure of
approx. -10 mbar.
3. Start test time of 1 minute on the timer.
4. Read off the pressure at the end of the test time.
The pressure difference must not exceed ±1 mbar.
Checking the opening pressure of the exhalation valve
1. Open the hose of the lung demand valve and connect it to
the medium-pressure connection of the test unit.
2. Press the right control lever until the exhalation valve opens.
3. Read the opening pressure and compare with the target
value:
The exhalation valve must open between +4.2 mbar and
5.7 mbar.
Testing low-pressure rise
1. Shut off lung demand valve.
2. Pull right control lever to generate a pressure of 0 mbar.
3. Start test time of 1 minute on the timer.
4. Read off the pressure at the end of the test time.
The pressure must not rise above 8 mbar.
Testing switching pressure and static positive pressure
1. Press the left control lever until the lung demand valve
switches on.
2. Read the low pressure gauge to check the negative
pressure at which the lung demand valve switches on.
The lung demand valve must open between -3.0 mbar
and -30 mbar.
3. After a few seconds read the next value (= static positive
pressure) at the low pressure gauge.
The pressure must be between +1 mbar and +3.9 mbar.
Testing static medium pressure and medium-
pressure rise
1. Press right control lever briefly twice.
2. Read the pressure at the medium-pressure gauge and
compare with the target value:
The pressure must be between 6 bar and 9 bar.
3. Start test time of 1 minute on the timer.
4. Read the medium pressure at the end of the test time.
The pressure must not rise by more than 0.7 bar or fall
more than 0.2 bar.
Performing high-pressure leak test
1. Close cylinder valve.
2. When the cylinder valve is fully closed, read the pressure
at the SCBA immediately.
3. Start test time of 1 minute on the timer.
4. Read off the pressure at the end of the test time.
The pressure must not fall more than 10 bar.
en
Use
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