Going in for a routine physical a few years ago I mentioned that the air sometimes seemed thin
when I walked up the hill in my backyard.
First, there was a chest X Ray and then a Pulmonary Function Test (PFT). I have asthma and the PFT test indicated a significant loss of capacity. I was shocked.
I had always thought that if I had a serious lung problem that it would be hard to inhale. I was completely wrong as asthma, emphysema, and bronchitis usually/always? reduce the ability to exhale.
Check this point on your own. One important quick test is to exhale as rapidly as possible and measure the peak flow rate
using a simple meter. The PFT makes a better measurement by measuring the maximum volume exhaled in 1 second and also makes several more detailed measurements.
I also had a big misconception about the structure of the lungs. I had pictured the lungs as largely hollow with convoluted structure around the outside. The lungs have no large hollow volume and are more like a sponge consisting of branching bronchial tubes, blood vessels, and about 300,000,000 alovei spherical air cavities.
If anyone suspects breathing problems have your lung function measured with a PFT.
My symptoms were not bad. Throughout I play tennis and can play singles. An inhaler makes a very noticeable difference if I, for example, exercise on an elliptical.
There is no clear trigger. I try to avoid dust especially the 'respirable' particle size that is too fine to see and gets into the lungs more than the big stuff. Vacuum cleaners do well catching the larger visible dust but they pass finer dusts to some degree back into the air. HEPA filter are probably best but they only claim to filter down to a certain size - 99.97% of particles 0.3 micrometers and larger
- that does not necessarily include much of the respirable particles that are smaller than 0.3 micrometers.
Information on particulates-
Presentation overall coverage of subject. See settling times.
How long do particulates float in the air? Scientific basis for settling times based from on air resistance of spherical bodies.