Test Method For Dynamic Respiratory Resistance And Performance Evaluation Of Civil Respirator

With the significant increase of the urban population and the rapid industrial development,the air quality in many big cities has deteriorated.In some areas the haze weather is getting worse and worse.Masks have become necessities for people to go out in polluted air.The detection and evaluation methods of respiration resistance of civil masks are still immature.The test methods used are simple and the experiments are carried out in static conditions,which can’t test and evaluate the breathing resistance of civil masks synthetically and dynamically.Based on the summary of the research status at home and abroad,this thesis studied the dynamic testing method and evaluation index system of breathing resistance of civil masks.A new method of objective dynamic test was proposed by simulating the continuous breathing process during the actual wear of the mask and collecting the dynamic changes of respiration resistance of the mask in real time.Based on the proposed test method,this thesis developed a dynamic objective test system for respiratory resistance of civil masks,including the establishment of simulation continuous respiratory system and respiratory resistance test module,the design of test system hardware circuit and test system software.Six evaluation indices,including the maximum inhalation resistance,maximum inhalation resistance,the average change rate of inhalation resistance,maximum change rate of inhalation resistance,the average change rate of exhalation resistance and maximum change rate of exhalation resistance,have been defined for the dynamic resistance performance of civil mask,derived from the source data of dynamic breathing resistance.Twelve typical types of civil masks with different characteristics have been tested with the prototype dynamic measurement system and the widely used static test device in China.The one-way ANOVA analysis was carried out to identify the significance of the differences of the indices among the test masks.The results show that each evaluation index is significantly different(P<0.05)among different test masks.Correlation analysis between dynamic measurement and static measurement was conducted.And the results show the static indices in dynamic experiment and the indices in static experiment are relevant.A comparative analysis of the results of static test and dynamic test in this study was conducted.And the impact of the respiratory valve,shape,material and the brand of civil masks were compared.The results show the dynamic index values of the masks with respiratory value are smaller than those without respiratory valve,the dynamic index value of the masks in cup shape are smaller than the fold,the dynamic index value of the cotton masks without valve are smaller than non-woven masks.And the resistance performance of masks in different brands is different.A comprehensive and dynamic testing method of respiration resistance of civil masks was proposed.The new measurement system is provided an objective method and device for the test of dynamic breathing resistance and performance evaluation of civil mask.