Dead space
1、 Applicable standards
GB 2626-2006 respiratory protective equipment - self suction filter type particulate respirator
GB 2890-2009 respiratory protection self inhalation filter gas mask
2、 Main purpose
The volume fraction of carbon dioxide re inhaled from the previous breath is used for the dead chamber performance test of self-priming filter gas mask.
3、 Equipment principle
Subtract the CO2 concentration in the environment from the CO2 concentration in the inhaled gas, and take the average value for three consecutive tests, which shall not be greater than 1%. So as to judge the performance of the mask dead cavity test device.
4、 Technical indicators
1. Simulated respiratory frequency modulation of respiratory simulator: 10-40 times / min
2. Regulating range of simulated tidal volume: 0.5-3.0l/min
3. The volume fraction of carbon dioxide gas source is 5.0 ± 0.1%
4. Carbon dioxide flowmeter range: no less than 40L / min
5. Carbon dioxide analyzer range: not less than 12%, accuracy not less than 0.1%
6. Electric fan: wind speed 0.5m/s
7. Respiratory rate: 20 times / min
8. Tidal volume: 1.5L
9. Power supply: AC220V 50Hz
10. Real time automatic calculation and display of volume fraction of CO2 in suction gas
11. Ht-8010 special control software controls test action
12. Hototech independently develops control board
13. The software has Chinese simplified, Chinese traditional and English language switching functions
14. The software supports data storage, historical data query, data export / printing, etc
15. Reports can be saved in word, Excel, PDF, JPG and other formats
5、 Test method
1. Check the detection system and make sure it is in normal working condition. Necessary measures shall be taken to wear the tested sample on the matched test head mould in a gas tight manner and prevent the mask from deformation.
2. Open the dead chamber detection device, continuously monitor and record the concentration of CO 2 in the suction gas and detection environment until it reaches a stable value.
3. Three samples of disposable mask shall be tested once respectively, and each sample of half mask or full mask shall be tested three times repeatedly. The test is valid only if the concentration of CO 2 in the test environment is greater than 0.1% (volume fraction), and the concentration of CO 2 in the test environment shall be deducted.
6、 Components
1. Ventilator, airflow sine wave curve, imported motor from Japan is selected, ventilator frequency can be set and adjusted, flow can be set and adjusted, ventilator simulates artificial respiration, and carries out the concentration detection, temperature and pressure detection of CO 12
2. Carbon dioxide concentration sensor, one for monitoring the carbon dioxide concentration in the mask and one for monitoring the carbon dioxide concentration outside the mask
3. Analysis system, self-made R & D operation sensitive, automatic control, friendly interface, easy to operate
4. Imported variable frequency small fan, standard requirement: 5m / s wind speed
5. CO2 flowmeter: the measuring range shall not be less than 40L / min.
6. High quality pressure reducing valve to control gas flow output
7. Imported high precision wind speed tester, 0.5m/s can measure very low air with high precision
9. The box body is painted, beautiful and corrosion-resistant
10. The volume fraction of CO2 is 5 ± 0.1%.
