Black Carbon and Ultrafine Particle Infiltration Through HVAC System

Details

• Personal Author:
  Fung CC ; Wong C ; Zhu Y
• Description:
  Objective: To identify the correlation of diesel exhaust and indoor air pollutants. Complaints of diesel exhaust odor within office spaces at the Fielding School of Public Health raised suspicion of infiltration through ventilation system, since diesel exhaust can cause premature mortality and increased cancer risk prompting administrative concern and scientific investigation. This 7 story, 2 basement building has roughly 1,800 occupants comprised of academic and administrative staff, and students. Methods: DustTraks, SMPS, Q-Trak, and Aethalometer measured simultaneously the indoor and outdoor air concentrations of PM2.5, ultrafine particles, carbon dioxide, and black carbon, respectively. Instruments placed inside offices measured indoor air concentrations. Instruments placed through a sealed window of the second floor office that faces the loading dock measured outdoor air concentrations. Twenty-four hour sampling was done from January 10-18, 2014. Time series of data and linear regression of outdoor and indoor concentrations were graphed. Results: Results indicate consistent infiltration of diesel exhaust due to diesel truck traffic in the loading dock where the HVAC is located. Spikes in indoor air pollutant concentrations are observed throughout the day that correspond to outdoor air pollutant concentration. Outdoor air concentrations and indoor air concentrations have similar trends. R-squared analysis of black carbon reached up to 0.63, PM2.5 peaked at 0.62, ultrafine particles was up to 0.93, and carbon dioxide's highest r-square was 0.86. Differences in correlation is explained by chemical and physical properties of ultrafine particles, PM2.5, black carbon, and carbon dioxide. Peaks in concentrations occurred during the presence of loading trucks and that the longer the trucks were in the loading dock, the higher the concentrations were. Conclusion: Administrative mitigation through stringent enforcement of vehicles emission standards allowed in the loading dock or controls implemented to change times that freight trucks are loading. Engineering controls include increasing ventilation and installing filters with higher MERV scores. [Description provided by NIOSH]
• Subjects:
  Air Pollution, Indoor Carbon Dioxide Environmental Monitoring Occupational Health Safety Ventilation
• Keywords:
  Air Sampling Automotive Emissions Carbon Black Carbon Dioxide Diesel Exhaust Indoor Air Pollution Ultrafine Particles Ventilation Systems
• Publisher:
  American Industrial Hygiene Association
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Abstract or Summary
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  8-9
• NIOSHTIC Number:
  nn:20055835
• Citation:
  AIHce 2015: American Industrial Hygiene Conference and Exposition, May 30 - June 4, 2015, Salt Lake City, Utah. Falls Church, VA: American Industrial Hygiene Association, 2015 May; :8-9
• CAS Registry Number:
  Carbon black (CAS RN 1333-86-4) ; Carbon dioxide (CAS RN 124-38-9)
• Federal Fiscal Year:
  2015
• Performing Organization:
  University of California Los Angeles
• Peer Reviewed:
  False
• Start Date:
  20050701
• Source Full Name:
  AIHce 2015: American Industrial Hygiene Conference and Exposition, May 30 - June 4, 2015, Salt Lake City, Utah
• End Date:
  20270630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:8f177a4cc760780dab09a640623f8ebecac15e24d6441372bdc2d24f277920d3572fee23f95681a1f01e778600a1e9bb9887040641b9842e8892a26908b850de
• Download URL:
  https://stacks.cdc.gov/view/cdc/213601/cdc_213601_DS1.pdf
• File Type:
  [PDF - 672.36 KB ]