Inventors:
Robert O. Crapo - Salt Lake City UT
Robert L. Jensen - Salt Lake City UT
Assignee:
Hans Rudolph, Inc. - Kansas City MO
International Classification:
G01N 33497
Abstract:
A calibration apparatus for checking the accuracy of DLco testing machines includes a pair of syringes mounted side by side in a frame and joined by a valve controlled gas passageway to a coupling adapted to mate with the testing machine. The first syringe receives gas from the testing machine and the second syringe has a chamber from which gas of a known concentration is returned to the testing machine. The chamber of the second syringe is flow connected by a valve to a source of test gas. The gas passageway is constructed in such a manner to reduce dead air space and to allow purging with test gas to eliminate contamination with ambient air or gas of previous tests.