A blower-door test measures envelope leakage at 50 Pa reference and is often used to compare homes and small buildings. It helps estimate what for mechanical engineers?

Choices

• (A) Refrigerant mass charge
• (B) Tower approach only
• (C) Effective infiltration / unintended OA load, then ventilation balance / right-sizing of OA equipment
• (D) Transformer inrush LRA of motor