Dru Burns

Date of Graduation

2016

Document Type

Thesis

Degree Type

MS

College

Statler College of Engineering and Mineral Resources

Department

Industrial and Managements Systems Engineering

Committee Chair

Steven E Guffey

Committee Co-Chair

Xinjian He

Committee Member

Ryan F LeBouf

Abstract

Evacuated canisters offer an opportunity to expand on the way volatile organic compounds (VOCs) are measured in indoor air quality investigations, industrial hygiene assessments, and emergency response scenarios. There is a growing need for alternative sampling methods for VOCs as traditional sorbent tube sampling methods may not adequately capture the multitude of chemicals present in mixed exposure environments due to sorbent-analyte specificity.;This study is part of a larger work designed to address this need across a suite of 17 VOCs. This study assesses generation and evaluation methods for the production of reference evacuated canister samples as part of an ASTM-style interlaboratory study. The interlaboratory study was designed to assess evacuated canister method performance for the development of a National Institute for Occupational Safety and Health (NIOSH) Manual of Analytical Methods protocol.;The reference canister samples were generated in two concentration ranges (part-per-million and part-per-billion) and at three nominal concentration levels within the two ranges. For the PPB range, samples were generated using either a flow-based dilution or combination pressure dilution and canister-to-canister transfer technique. For the PPM range, samples were generated by either the combination pressure dilution and canister-to-canister transfer technique, or a manifold dilution method. The reference canister samples were analyzed via gas chromatography-mass spectrometry (GC-MS). The performance of three preparation methods and three analytical methods were assessed by the NIOSH 95% confidence interval on accuracy criterion.;Results indicate that method accuracy is concentration dependent with respect to certain combinations of analytical method, preparation technique, and analyte. Some sample preparation techniques were found to be better for certain groups of compounds and at certain concentration ranges. All 17 VOCs passed the NIOSH accuracy criterion for the PPM range when prepared using the pressure dilution technique and analyzed via a 1 cc loop injection into a GC-MS. For the PPB range of concentration levels, 15 VOCs passed the NIOSH accuracy criterion when prepared by the pressure dilution method and analyzed via a 250 cc, cryogenically concentrated injection into a GC-MS.

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