A mask fit tester is a device used to evaluate the fit of a mask during wearing. The following are some requirements for the detection parameters of the mask fit tester:
1. Test pressure: Test pressure refers to the pressure applied to the mask, simulating the pressure that the wearer receives when actually using the mask. The test pressure is usually specified by the test standard, common values include 10Pa, 20Pa and 30Pa.
2. Airflow rate: The mask fit tester will pass a certain amount of airflow to simulate the airflow generated by breathing when wearing it. Airflow rates are usually specified by test standards, and common values include 30L/min, 70L/min, and 95L/min.
3. Leakage measurement: The fit tester will measure the leakage of the mask, that is, the amount of gas leaked from the edge or other parts of the mask when the mask is subjected to a certain pressure and airflow. Leakage is usually measured in ml/min or ml/s.
4. Leak location: The tester usually also records the location of the mask leakage, that is, where the detected air leakage is mainly concentrated, such as around the nose, mouth, jaw or face.
5. Fit rating: According to the leakage result and the location of the leak, the fit of the mask can be rated as different levels, such as excellent, good, fair or unqualified. Rating criteria are usually provided by test standards or related specifications.
6. Test time: The time for the mask fit test is usually specified by the test standard, which may be a test within a specific period of time or a specific number of breathing cycles.
7. Temperature and humidity: Mask fit testing is usually performed under specific environmental conditions, including temperature and humidity. These conditions may vary according to the requirements of the test standard.
It should be noted that the specific parameter requirements of the mask fit tester may vary depending on the test standard, purpose and application. Mask fit testers are usually calibrated and verified in accordance with relevant standards to ensure that the test results are accurate and reliable, and are used to guide mask design and production as well as quality control.