@exsibilation @FinchTH I'm not sure that in some cases with poorly fitting masks the output efficiency isn't worse. On inflow you have the suction effect. But yes it is additive (as is vent/filt). Still, 90% out and 90% in is a LOT better than 30% out and 30% in.
@exsibilation @FinchTH 我不确定在某些情况下，口罩的拟合效果不佳，输出效率不会变差。在流入时，您会产生吸力。但是是的，它是添加剂（就像通风/过滤一样）。尽管如此，90% 的输出和 90% 的输入比 30% 的输出和 30% 的输入要好很多。