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[Volatile organic compounds concentrations and sources inside new air-conditioned bus]
Ke-Wei You1, Yun-Shan Ge, Yi-Xin Qian
1School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081, China. awei810715@bit.edu.cn
Huan Jing Ke Xue= Huanjing Kexue
|July 16, 2008
Summary
New buses contain 33 volatile organic compounds (VOCs), primarily alkenes and aromatics, exceeding 52.5 mg/m3. These emissions originate from interior materials like plastics and foams, impacting air quality.
Area of Science:
- Environmental Chemistry
- Analytical Chemistry
- Material Science
Context:
- Vehicle cabin air quality is crucial for passenger health.
- New vehicles, particularly buses, can emit significant levels of volatile organic compounds (VOCs).
- Understanding VOC profiles is essential for assessing indoor air pollution in transportation.
Purpose:
- To determine the distribution and concentration of VOCs in new air-conditioned buses.
- To identify the specific chemical compounds and their quantities present in the bus cabin.
- To pinpoint the primary sources of these VOC emissions within the vehicle.
Summary:
- Thermal desorption-gas chromatography-mass spectrometry (GC/MS) identified 33 VOCs in new 53-seat buses, with alkenes and aromatic compounds being dominant.
- Key compounds included decane, 3-methylhexane, and heptane, with total volatile organic compounds (TVOC) exceeding 52.5 mg/m3.
- Emissions primarily stem from off-gassing and degradation of interior materials such as plastics, foams, adhesives, and sealants.
Impact:
- Provides critical data on indoor air quality in public transportation.
- Highlights the contribution of cabin materials to VOC pollution.
- Informs strategies for reducing VOC exposure in vehicle environments.
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