Peak flow rate in relation to forced expiratory volume in hemp workers

Žuškin, E., and Valić, F. (1971).Brit. J. industr. Med.,28, 159-163. Peak flow rate in relation to forced expiratory volume in hemp workers. Measurements of the forced expiratory volume in one second (FEV_1·0) and the peak expiratory flow rate (PEF) were made in 99 non-smoking female hemp workers before and after the shift. A significant mean reduction of both FEV_1·0 and PEF (P<0·01) over the shift was found in workers both with and without byssinosis but the relative reductions of PEF were more pronounced (FEV_1·0 15·3%; PEF 20·8%). There was a significant positive correlation (P<0·01) both between absolute FEV_1·0 and PEF values measured before work (with byssinosis r = 0·605; without byssinosis r = 0·461), and between FEV_1·0 and PEF changes over the shift (with byssinosis r = 0·725; without byssinosis r = 0·631). There was also a significant correlation between FEV_1·0 and PEF changes following Alupent inhalation after the shift with more pronounced effects on PEF. The coefficients of variation in FEV_1·0 and PEF measurements (by the Bernstein type spirometer and the Wright peak flow meter) proved approximately equal.