CDC logoSafer Healthier People CDC HomeCDC SearchCDC Health Topics A-Z
NIOSH - National Institute for Occupational Safety and Health

Skip navigation links Search NIOSH  |  NIOSH Home  |  NIOSH Topics  |  Site Index  |  Databases and Information Resources  |  NIOSH Products  |  Contact Us

NIOSH Program Portfolio

 

Manufacturing

NORA Manufacturing Sector Strategic Goals

927ZJGC - Interferent Effects on Organic Vapor Monitor Performance

Start Date: 10/1/2009
End Date: 9/30/2012

Principal Investigator (PI)
Name: Christopher Coffey
Phone: 304-285-5958
Organization: NIOSH
Sub-Unit: DRDS
Funded By: NIOSH

Primary Goal Addressed
5.0

Secondary Goal Addressed
None


Attributed to Manufacturing
50%

Project Description

Short Summary

The proposed study will investigate the effects of interferents and environmental conditions on the performance of DROVMs when sampling a specific agent of interest. The objectives of this project are to (1) document the performance of DROVMs under a variety of environmental conditions; (2) determine if calibration can be used to enhance DROVM performance and if so, provide documented methods for calibration to the stakeholders using DROVMs; and (3) provide more guidance for handling interferent effects especially for those situations with unknown hazards and the user does not have the time to ensure proper calibration the DROVM readings can be used even when the user knows that the numbers may not be accurate.

This project is contributing to the NIOSH program specifically the Agriculture, Forestry, and Fishing, Manufacturing and Public Safety Sectors and the Exposure Assessment, Emergency Preparedness and Response, Respiratory Diseases, and Cancer, Reproductive, and Cardiovascular Diseases Cross-Sectors.

The major outcome of this project will be new consensus standards on the performance and validation of direct-reading methods and instrumentation for first responders based upon the research results of this project. The outputs will be presentations at national conferences and peer-reviewed manuscripts detailing the results of each of the three phases.



Description

The study is investigating the effects of interferents and environmental conditions on the performance of DROVMs when sampling a specific agent of interest. The objectives of this project are to: (1) document the performance of DROVMs under a variety of environmental conditions; (2) determine if calibration can be used to enhance DROVM performance and if so, provide documented methods for calibration to the stakeholders using DROVMs; and (3) provide more guidance for handling interferent effects especially for those situations with unknown hazards and the user does not have the time to ensure proper calibration the DROVM readings can be used even when the user knows that the numbers may not be accurate.

This study will evaluate three MIRAN SapphIRe Portable Ambient Air Analyzers and Century Portable Toxic Vapor Analyzers (TVA) in the three phases. In the first phase, the performance of the DVROMs will be compared to NIOSH Method 1500 and an evacuated canister method when calibrated per the manufacturers’ instructions vs. calibration with the gas/vapor of interest. The instruments will be calibrated per the manufacturer’s instructions. For the second series of tests, both instrument groups will be calibrated using four concentrations of cyclohexane (i.e., the vapor of interest). Each series of tests will be conducted at different temperatures and RHs to determine their effect on the DROVM performance. This phase will be completed in calendar year 2010.

In the second phase, the performance of the DROVMs to will be compared to NIOSH Method 1500 and an evacuated canister method when calibrated at approximately normal office/laboratory environmental conditions (21°C and 50% RH) vs. the environmental conditions expected at the sampling site. This phase will consist of two series of tests. For the first series of tests, the instruments will be calibrated per the manufacturer’s instructions at 21°C and 50% RH. For the second set of tests, the instruments will be calibrated at the combination of temperature and humidity at which the instruments’ performance was most different from the charcoal tubes and evacuated canisters. Both instrument types will be calibrated per the manufacturer’s instructions. After each type of calibration, tests will be conducted at the combination of temperature and humidity at which the instruments’ performance was most different from the charcoal tubes and evacuated canisters. Four concentrations of cyclohexane will be utilized. Charcoal sorbent sample tubes will be used and analyzed in accordance with NIOSH Method and two 400 cc evacuated silonite-coated stainless steel canisters equipped with a Passive Canister as standards to compare the DROVM performance. Each condition will be tested five times. This phase will be completed in calendar year 2011.

In third phase, the performance of the SapphIRes and TVAs will be determined when sampling cyclohexane with and without interferents. Simulants for the interferents will be used: hexane, 2-butanone, trichloroethylene, and toluene. These contaminants are common chemicals which may be encountered during emergency response and represent different classes of organic compounds (straight-chain hydrocarbons, ketones, chlorinated hydrocarbons, and aromatics) which may elicit different instrument responses. In this phase, the instruments will be tested in the following combination of vapors: cyclohexane and hexane, cyclohexane and 2-butanone, cyclohexane and trichloroethylene, cyclohexane and toluene, and cyclohexane, hexane, 2 -butanone, trichloroethylene, and toluene. Four concentrations of cyclohexane will be used (0, 30, 150, 300, and 475 ppm). Each of the four vapor concentrations will have multiple proportions of cyclohexane: interferents. The ratios will be 33%:67%, 50%:50%, and 67%:33% equaling each of the four concentrations. This will enable the determination of the effect of the interferents on DROVM performance. The instruments will be calibrated using the procedure determined to provide the closest DROVM performance to the charcoal tubes and evacuated canisters in phase 1. The temperature and RH to be used in this phase will be the combination from phase 2 that affects DROVM to the greatest degree. Each condition will be run five times. The DROVM performance determined in this phase will be compared to the DROVM performance for cyclohexane only as determined in the previous phases. This phase will be completed in calendar year 2012.



Mission Relevance

This project has relevance to the work being conducted by the Department of Homeland Security (DHS). At the DHS, Science & Technology Directorate sponsored Town Hall Meeting on Threat Detection Technologies, Mr. Bert Coursey, Standards Executive for DHS, stated in his opening presentation: “Technologies that are developed and validated according to consensus based standards prevent the sale of ‘snake-oil’ products to federal, state and local governments and facilities-protection communities.”



Page last updated: June 3, 2011
Page last reviewed: May 23, 2011
Content Source: National Institute for Occupational Safety and Health (NIOSH) Office of the Director

 

NIOSH Program:

Manufacturing