@davetone007 @MeetJess Problem with insert filters in untested designs is the air can go around the filter, even if the filter is very good. I wouldn't use it without a quantitative fit test to know the actual protection factor.
@davetone007 @MeetJess 在未经测试的设计中插入过滤器的问题是空气可以绕过过滤器，即使过滤器非常好。如果没有定量拟合测试来了解实际保护系数，我不会使用它。