Noise Criterion Curves - Lennox MMA018SM4 Service Manual

3. Noise Criterion Curves

Sound is measured 4.92 ft (1.5m) away from the center of the air handler. Data is valid and gathered in free field and
nominal operation conditions. The sound level will vary based on where the unit is installed.
Acoustic pressure OdB = 20μPa
MMA018
6.56ft (2m)
Air Handler
Figure 8. Noise Measurement - Concealed Duct
3.28ft (1m)
4.92ft (1.5m)
MMA024
15