FFP2 rated masks

National standards for dust masks vary from country to country, and comparisons are focused on each.

In the FFP2 standard, the mask traps dust at a rate equal to or greater than 94%, which is one percentage point less than the N95 trap rate, however, the air flow rate per minute through the test is different, 95 liters per minute for the European standard and 85 liters per minute for the American standard.

At the same time, a high or low impedance value represents the degree to which the mask impedes respiration when used, with higher values impeding respiration and the comfort level of the two being different.

Source: https://www.unisourcesgroup.com/news/60.html