New devices: the McDermott spirometer.
The assessment of a new bellows spirometer against a water spirograph showed: slight alinearity, minimal overestimation of FVC (1.7%) and underestimation of FEV 1-0 (2.9%) as well as of the ratio FEV 1-0/FVC (4.8%). The main advantages of the instrument are: lightness, easy operation, ruggedness and low cost; it seems mainly indicated for use in large scale field surveys.
D013147:Spirometry / Q000295:instrumentation*