introduction to ozone instrumentation and analysis

Introduction to OzoneInstrumentation and Analysis

Nate Herbst,

Southern Ute Indian Tribe

Joe Hameed, ITEP/TAMS

2

Intro to Instruments and Analysis

• What type of instrumentation is used?• What type of analysis is employed?• How is the analysis performed?• How does the analyzer work?

3

Ozone Analyzer Basics

• Design based on U.V absorption• U.V photometry [O3]

Some pictures of the Thermo 49C

4

Theory of Analysis

• Ozone absorbs 240nm U.V radiation• Dual cell technique ambient and zero

absorptions• Zero and ambient absorptions compared• Ozone concentration = ambient absorption –

zero absorption

5

U. V. Photometric Absorption

• Remember: ozone absorbs U.V.

Ozone absorbing U.V radiation.

Animation by NASA.

Zero air Ambient airU.V. Lamp Detector

Amount of U.V light leaving cell #1 corresponds to [O3]

Amount of U.V light leaving cell #2 provides your blank

Photo courtesy of University of

Wisconsin General Chemistry Class.

6

Ozone Analyzer Optical System (Thermo Env. 49C)