| FEC | forced expiratory capacity; free erythrocyte coproporphyrin; freestanding emergency center; Friend e... |
|---|---|
| FEF | forced expiratory flow |
| FEF50 | forced expiratory flow at 50% of forced vital capacity |
| FEF50/FIF50 | ratio of expiratory flow to inspiratory flow at 50% of forced vital capacity |
| FEFV | forced expiratory flow volume |