As applications requiring gas mixtures become more sophisticated, the mixtures required become progressively more complex. Permeation tubes can supply miniscule flows of a wide range of analyte vapors...

Teflon® permeation tubes are a proven method for making trace concentration gas mixtures when used in their equilibrium state. Permeation rates are established by a gravimetric weight loss method...

Analyzers for monitoring water quality in processor waste water streams require calibration with liquid standards. Traditional techniques for preparing these standards are cumbersome and often...

Gas sensor sensitivity levels have increased in equipment where atmospheric conditions, such as relative humidity, directly affect test results. Calibrating for changes in relative humidity in trace...

When the analysis is for product quality monitoring or personnel safety assurance, the concentrations measured are often in the ppb to low ppm levels. At these low concentrations, the loss of analyte...

Methods are compared for preparing calibration standards for volatile organic compound analysis. Traceability is compared for static and dynamic methods such as direct mechanical dilution, diffusion...

Moisture standards have traditionally been prepared by techniques which saturate the gas at known conditions. Preparing standards at trace concentrations (low ppm, ppb) requires saturation at...

The measurement of trace concentrations of water vapor in reactive gases has become very important in the semiconductor manufacturing industry. Techniques for measuring low ppm and ppb moisture in...

Maintaining reliable standards for trace sulfur compounds in an olefin matrix is a common problem in industrial quality assurance. Using permeation tubes to dynamically blend the required mixtures...