Dead space tester for masks

This device is designed and manufactured according to the standards GA124 and GB2890 for testing the dead space of positive pressure fire fighting air breathing apparatus. The testing principle is determined by measuring the CO2 content in the inhalation gas.

Technical specifications

1. Working environment: CO2 gas concentration in the surrounding air ≤ 0.1%

2. CO2 gas source: CO2 gas volume fraction (5±0.1)%

3. CO2 flow meter: flow rate range: 0-50L/min, accuracy: class 2.5. 4.

4. Equipped with CO2 analyzer: range 0-12%, accuracy class 1; CO2 sensor of British Servomex brand.

5. Equipped with a CO2 analyser: range 0-5%, accuracy class 1; the CO2 sensor is a British Servomex brand.

6. Equipped with a hand-held anemometer, range: 0-10 m/s, accuracy: ±(0.1m/s+5% of measured value) For the measurement range (0-2m/s), the anemometer should be of German Detu brand.

7. Equipped with floor standing electric fan.

8. The artificial lung breathing frequency can be adjusted from (10 to 40) times/min and the breathing tidal volume can be adjusted from (0.5 to 3.0) L.

9. The apparatus is operated by computer, using Detection control program and ZWH4500 acquisition control card can realize the functions of program control, data acquisition, test result calculation and print report, data storage and historical data query.

10. Total power supply: AC220V, power 500W.

Structure principle

The main components of the test device include: test head mould, mechanical artificial lung with solenoid valve, connecting pipe, flow meter, CO2 gas analyser and control system.

The test device is driven by the low-speed motor of the testing device through the control system, which drives the artificial lung to make reciprocating movements to simulate the actual human breathing process. The push stroke is equivalent to inhalation and the return stroke to exhalation. For the head mould in the upper part of the cabinet, these two processes complete a breathing process. A certain amount of highly concentrated CO2 is fed in at the same time as the inhalation and the whole breathing process is detected using a CO2 gas analyser.