Formaldehyde emissions from ventilation filters under different relative humidity conditions

Details

• Personal Author:
  Chang A ; Chen W ; Cohn S ; Destaillats H ; Fisk WJ ; Kumagai K ; Miller R ; Sidheswaran M ; Sullivan D
• Description:
  Formaldehyde emissions from fiberglass and polyester filters used in building heating, ventilation, and air conditioning (HVAC) systems were measured in bench-scale tests using 10 and 17 cm(2) coupons over 24 to 720 h periods. Experiments were performed at room temperature and four different relative humidity settings (20, 50, 65, and 80% RH). Two different air flow velocities across the filters were explored: 0.013 and 0.5 m/s. Fiberglass filters emitted between 20 and 1000 times more formaldehyde than polyester filters under similar RH and airflow conditions. Emissions increased markedly with increasing humidity, up to 10 mg/h-m(2) at 80% RH. Formaldehyde emissions from fiberglass filters coated with tackifiers (impaction oils) were lower than those from uncoated fiberglass media, suggesting that hydrolysis of other polymeric constituents of the filter matrix, such as adhesives or binders was likely the main formaldehyde source. These laboratory results were further validated by performing a small field study in an unoccupied office. At 80% RH, indoor formaldehyde concentrations increased by 48-64%, from 9-12 µg/m(3) to 12-20 µg/m(3), when synthetic filters were replaced with fiberglass filtration media in the HVAC units. Better understanding of the reaction mechanisms and assessing their overall contributions to indoor formaldehyde levels will allow for efficient control of this pollution source. [Description provided by NIOSH]
• Subjects:
  Air Movements Air Pollutants, Occupational Air Pollution, Indoor Filtration Formaldehyde Glass Humidity Occupational Health Safety Ventilation
• Keywords:
  Air-contamination Air-filters Air-flow Emission-sources Fibrous-glass Filter-materials Filters Formaldehydes Relative-humidity Ventilation-equipment Ventilation-systems

  More +
• ISSN:
  0013-936X
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  47
• Issue:
  10
• NIOSHTIC Number:
  nn:20044013
• Citation:
  Environ Sci Technol 2013 May; 47(10):5336-5343
• Contact Point Address:
  Hugo Destaillats, Lawrence Berkeley National Laboratory, Indoor Environment Group, Berkeley, CA
• Email:
  HDestaillats@lbl.gov
• CAS Registry Number:
  Formaldehyde (CAS RN 50-00-0)
• Federal Fiscal Year:
  2013
• Performing Organization:
  University of California-Lawrence Berkeley Laboratory
• Peer Reviewed:
  True
• Start Date:
  20090915
• Source Full Name:
  Environmental Science and Technology
• End Date:
  20120914
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:1af2c4b44336d9690bd24eeba0018a76473c33d27f202dc686b82d31be72e50ad4fe88bbe77ef584fffd23ca532c58219fafe78d448d7a4f708230f4ce103e9f
• Download URL:
  https://stacks.cdc.gov/view/cdc/199869/cdc_199869_DS1.pdf
• File Type:
  [PDF - 891.32 KB ]