Table 1.
Tested filter materials.
| Material | Surgical face mask | Hygienic mask | Toilet paper | Paper towel | Coffee filter |
|---|---|---|---|---|---|
| Pressure drop at 60 l/min [mbar] | 0.2 | a | 0.3 | 0.3 | 1.8 |
| Pressure drop at 90 l/min [mbar] | 0.4 | a | 0.6 | 0.7 | 4.0 |
|
| |||||
|
Material |
Microfibre cloth |
Fleece |
Vacuum cleaner bag |
FFP3 mask with valve |
Halyard H600 |
| Pressure drop at 60 l/min [mbar] | 7.7 | 0.1 | 2.0 | b | 1.4 |
| Pressure drop at 90 l/min [mbar] | 17.2 | 0.2 | 4.5 | b | 3.1 |
a
Not measured.
b
Not available. Due to the valve and the resulting inhomogeneous flow field, the volume flow rate could not be determined with the method applied.