Question: how to check if your lungs are healthy at home?
Answer: Set the pointer on the gauge of the peak flow meter to 0 (zero) or the lowest number on the meter.
Attach the mouthpiece to the peak flow meter.
Stand up to allow yourself to take a deep breath. ... 
Take a deep breath in. ... 
Breathe out as hard and as fast as you can using a huff. ... 
Note the value on the gauge.