meter-, metro-, metr-, -metrical, -metrically, -metron, -metric, -metrist, -meter, -meters, -metry, -metre
2. The measurement of carbon dioxide in a volume of gas.
The most common monitoring units are based on the selective absorption of infrared light by carbon dioxide and water vapor.
Capnometries usually work on the principle that carbon dioxide absorbs infra-red radiation. A beam of infra-red light is passed across the gas sample to fall on a sensor. The presence of carbon dioxide in the gas leads to a reduction in the amount of light falling on the sensor, which changes the voltage in a circuit.
Capnometry measures the concentration of carbon dioxide (which provides information on blood flow) through the lungs, which then goes on to other organs.
2. A device consisting of two thermometers, one a dry bulb and the other a wet bulb.
Both are heated to 110°F (43.3°C) and the time required for each thermometer to fall from 100° to 90°F (37.8° to 32.2°C) is noted. The dry bulb gives the cooling power by radiation and convection, the wet bulb by radiation, convection, and evaporation.
From this, the temperature as it affects the body can be deduced; or it is a measure of the heat content of the environment that takes into account air movement as well as temperature.
The telescope in the cathetometer is raised or lowered in order to see the objects or surfaces, and to determine the differences in vertical height which are then shown on the graduated standard.