Reading Flow volume loops

... can be somewhat confusing.  the axis are all screwed up in my opinion... thats what i determined after looking at this for the past 10 minutes.

Anyhow, you wanna look at things like TLC (total lung capacity), FEV1 (amount of air the person can blow out in the first second), and FEF50%.
FEF50% -- forced expiratory flow (the average speed of air coming out of the lung during middle portion of expiration)... which is low in both obstruction and restriction (but especially in an obstruction).
TLC is increased in obstructive.
 

A- normal
B-obstructive
C-restrictive
D-obstruction of upper airway.