Key mask performance metrics typically include filtration efficiency and breathing resistance (differential pressure). Different standards and scenarios define conditioning, aerosol parameters and flow rates differently.

How to interpret results

• Resistance: affected by structure, moisture content and electrostatic treatment; relates to comfort and airflow.
• Filtration: impacted by fiber structure, charge retention and manufacturing stability; results are not directly comparable across different methods.

To minimize inter-lab variation, align on the exact standard version and test conditions, and keep retained samples for re-checks.

Note: final judgement follows the applicable standard and report.