FEF200-1200, FEF25-75% and FEF75-85% in non-smokers of either sex and in male smokers residing at an altitude of 2150 M above MSL in Himachal Pradesh.

Forced expiratory flow (FEF) rates were determined for 170 (130 males and 40 females) healthy adults of Himachal Pradesh in the age group of 19-26 years for males and 19-22 years for females. The subjects had been staying at an altitude of 2150 M above mean sea level (MSL) for at least three years prior to the conduct of the study. FEF200-1200, FEF25-75% and FEF75-85% were found to be high as compared to those reported from most other parts of the country. The results were found comparable with those reported from certain populations in U.S.A. Further, the flow rates of the non-smoker males were compared with those of the male smokers. FEF75-85% in smokers was significantly less than that of non-smokers, whereas the differences in FEF200-1200 and FEF25-75% were found to be nonsignificant.