[NORMAC--a simple instrument to measure the inspiratory and end- expiratory concentrations of halothane, enflurane, and isoflurane. Clinical use and laboratory investigations].

In 47 gas mixtures particularly made for that purpose the concentration of halothane, enflurane, or isoflurane was estimated with Normac; the estimated and measured values were found to be identical on the average. To verify precision, 40 measurements of one specimen were performed; the standard deviation was 0.03 vol-% (ca. 1% relative error). Any influence of the carrier gas components O2, N2, N2O, and H2O proved to be negligible. The practical clinical application of the apparatus was easy and without malfunctions.