Chamber Evaluation of a Portable GC with Tunable Retention and Microsensor-Array Detection for Indoor Air Quality Monitoring

Details

• Personal Author:
  Jin C ; Lu CJ ; Zellers ET
• Description:
  The evaluation of a novel prototype instrument designed for on-site determinations of VOC mixtures found in indoor working environments is described. The instrument contains a miniature multi-stage preconcentrator, a dual-column separation module with pressure-tunable retention capabilities, and an integrated array of three polymer-coated surface acoustic wave sensors. It was challenged with dynamic test-atmospheres of a set of 15 common indoor air contaminants at parts-per-billion concentrations within a stainless-steel chamber under a range of conditions. Vapours were reliably identified at a known level of confidence by combining column retention times with sensor-array response patterns and applying a multivariate statistical test of pattern fidelity for the chromatographically resolved vapours. Estimates of vapour concentrations fell within 7% on average of those determined by EPA Method TO-17, and limits of detection ranged from 0.2 to 28 ppb at 25 degrees C for 1 L samples collected and analyzed in <12 min. No significant humidity effects were observed (0-90% RH). Increasing the chamber temperature from 25 to 30 degrees C reduced the retention times of the more volatile analytes which, in turn, demanded alterations in the scheduling of column-junction-point pressure (flow) modulations performed during the analysis. Reductions in sensor sensitivities with increasing temperature were predictable and similar among the sensors in the array such that most response patterns were not altered significantly. Short-term fluctuations in concentration were accurately tracked by the instrument. Results indicate that this type of instrument could provide routine, semi-autonomous, near-real-time, multi-vapour monitoring in support of efforts to assess air quality in office environments. [Description provided by NIOSH]
• Subjects:
  Air Pollution Air Pollution, Indoor Environmental Monitoring Humidity Occupational Health Safety Temperature Workplace
• Keywords:
  Air-quality Air-quality-control Air-quality-measurement Air-quality-monitoring Environmental-health-monitoring Gas-chromatography Monitoring-systems Temperature-effects Work-environment Workers
• ISSN:
  1464-0325
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Michigan ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  270-278
• Volume:
  8
• Issue:
  2
• NIOSHTIC Number:
  nn:20030276
• Citation:
  J Environ Monit 2006 Feb; 8(2):270-278
• Federal Fiscal Year:
  2006
• Performing Organization:
  University of Michigan, Ann Arbor
• Peer Reviewed:
  True
• Start Date:
  19980930
• Source Full Name:
  Journal of Environmental Monitoring
• End Date:
  20060531
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:a88cbcb6c2784e146b934bbaed307ceba03246621424599ac7a6454bb4decf447a878db7e5b438e97c9e5333dd3c696bb90ff173f065656bf9a4b97e75514106
• Download URL:
  https://stacks.cdc.gov/view/cdc/190992/cdc_190992_DS1.pdf
• File Type:
  [PDF - 704.27 KB ]