Index | Weight (g) | Circumference (mm) | Length (mm) | Hardness (mm) | Filter air permeability (%) | Open resistance (Pa) | Total ventilation rate (%) |
---|---|---|---|---|---|---|---|
Weight | 1.000 | ||||||
Circumference | 0.417** | 1.000 | |||||
Length | 0.011 | − 0.072* | 1.000 | ||||
Hardness | 0.498** | 0.162** | 0.073* | 1.000 | |||
Filter air permeability | 0.268** | 0.102** | 0.041 | 0.184** | 1.000 | ||
Open resistance | 0.519** | 0.224** | 0.073* | 0.325** | − 0.048 | 1.000 | |
Total ventilation rate | 0.565** | 0.265** | 0.073* | 0.342** | 0.838** | 0.25** | 1.000 |