RESUMEN
A novel controlled test atmosphere system was developed to generate multiple concentrations of gases and vapors simultaneously. It was used successfully to study the effectiveness of two air monitoring methods to analyze for various organic compounds. Three concentrations were generated simultaneously to determine the methods' performance. This was accomplished in a single run, requiring one day, greatly improving validation efficiency. Prior to development of this system, a separate test run was required at each concentration requiring three days. Essential elements of the system include: dynamic serial dilution of the air stream to produce three concentrations; all inert surface construction (Teflon, glass, and stainless steel); diffusion/permeation tube generation with multicompound capability; low pressure drop by use of large tubing and low pressure differential mass flow meters.
Asunto(s)
Contaminantes Atmosféricos/análisis , Calibración , Cromatografía de GasesRESUMEN
The industrial hygiene calibration manifold provides a continuous, stable, dynamic, reproducible vapor sample in the concentration range of fractional to thousands of parts per million. The principle of operation is the gravimetric determination of the sample diffusion or permeation rate and the measurement of total volumetric flow. The manifold consists of the following components: an organic-free air system, vapor jacketed diffusion-permeation chamber, jacketed multicomponent Venturi-type mixing manifold, exponential dilution flask and jacketed sampling manifold. This manifold can be used to validate or calibrate various industrial hygiene analyses such as charcoal and detector tube technology, impinger techniques, respirator cartridge testing, and various survey instruments.