This method measures the air change rate of the std type oven as follows:
N=
3590 (X-Y)x2
VxDxT
where:
N: number of changes of air per hour
X: Power consumption during air change (W)
Y: Power consumption during no air change (W)
V: total volume of oven (cm3)
D: Density of oven ambient air (g/cm3)
T: Temperature difference inside/outside oven (°C)