To limit the probability that the air leakage rate through the building envelope measured while mechanical equipment is operating as intended will not be adjusted in the energy model calculations, which could lead to omission of accounting for air leakage through mechanical equipment, which could lead to inaccuracy of the air leakage rate used, which could lead to inaccuracy of the model, which could lead to overestimation of the energy used by the reference building or underestimation of the energy used by the proposed building, which could lead to excessive use of energy, which could lead to an unacceptable effect on the environment.