Tao Huai

Dr. Tao Huai is Chief of Freight Emissions Assessment and Research Branch in the Monitoring & Laboratory Division at the California Air Resources Board.  Dr. Huai has extensive experience working in the field of vehicle emissions research and AB32 GHG regulation development, with nearly 10 years at ARB.  He is currently responsible for developing a comprehensive and unified emissions testing and research program for heavy-duty trucks and other freight related sources to support ARB’s mobile source regulatory programs and sustainable freight strategies. His scientific contributions include more than two dozen peer-reviewed journal publications and various invited technical presentations. 


  • PhD, Chemical and Environmental Engineering, University of California, Riverside, CA
  • MS, Management Science and Engineering, Tsinghua University, Beijing, China
  • BS, Thermal (Mechanical) Engineering, Tsinghua University, Beijing, China

Areas of Interest

Vehicle Emissions Research and Testing, Environmental Public Policy, Climate Change Mitigation.

Selected Publications

  • Quiros, D., Yoon, S., Dwyer, H., Collins, J., Zhu, Y.F., Huai, T. (2014) Measuring Particulate Matter Emissions during Parked Active Diesel Particulate Filter Regeneration of Heavy-Duty Trucks. Journal of Aerosol Science. 73, 48–62. 
  • Zheng, Z., Durbin, T.D., Xue, J., Johnson, K.C., Li, Y., Hu, S., Huai, T., Ayala, A., Kittelson, D.B., Jung, H.S. (2014). Comparison of Particle Mass (PM) and Solid Particle Number (SPN) Emissions from a Heavy-Duty Diesel Vehicle under On-Road Driving Conditions and a Standard Testing Cycle. Environmental Science & Technology. 48 (3): 1779–1786. 
  • Hu, S., Zhang, S., Sardar, S., Chen, S.Y., Dzhema, I., Huang, S.M., Quiros, D., Sun, H.W., Laroo, C.A., Sanchez, L.J., Watson, J., Chang, M-C.O., Huai, T., Ayala, A. (2014). Evaluation of Gravimetric Method to Measure Light-duty Vehicle Particulate Matter Emissions at Levels below One Milligram per Mile (1 mg/mile). SAE Tech. Paper 2014-01-1571. 
  • Hu, S., Herner, J.D., Robertson, W., Kobayashi, R., Chang, M-C.O., Huang, S., Zielinska, B., Kado, N., Collins, J., Rieger, P., Huai, T., Ayala, A. (2013). Emissions of Polycyclic Aromatic Hydrocarbons (PAH) and Nitro-PAH Emissions from HDDV with Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR). Journal of the Air & Waste Management Association. 63(8):984–996. 
  • Zheng, Z., Durbin, T.D., Karavalakis, G., Johnson, K.C., Chaudhary, A., Cocker, D.R., Herner, J.D., Robertson, W.H., Huai, T., Ayala, A., Kittelson, D.B., Jung.H.S. (2012). Nature of Sub-23-nm Particles Downstream of the European Particle Measurement Programme (PMP) - Compliant System: A Real-Time Data Perspective. Aerosol Sci. Technol., 46(8):886-896. 
  • Herner, J. D., Hu, S., Robertson, W. H., Huai, T., Chang, M-C. O., Rieger, P., Ayala, A. (2011). Effect of Advanced Aftertreatment for PM and NOx Reduction on Heavy-duty Diesel Engine Ultrafine Particle Emissions. Environmental Science & Technology. 45(6):2413-2419. 
  • Dwyer, H., Ayala, A., Zhang, S., Collins, J., Huai, T., Herner, J., Chau, W. (2010). A Study of Emissions from a Euro 4 Light Duty Diesel Vehicle with the European Particulate Measurement Program. Atmospheric Environment. 44(29), 3469-3476. 
  • Hu, S., Herner, J. D., Shafer, M., Robertson, W., Schauer, J. J., Dwyer, H., Collins, J., Huai, T., Ayala, A. (2009). Metals Emitted from Heavy-duty Diesel Vehicles Equipped with Advanced PM and NOx Emission Controls. Atmospheric Environment. 43(18), 2950-2959. 
  • Durbin, T.D., Miller, J.W., Younglove, T., Huai, T., Cocker, K. (2007). The Effects of Fuel Ethanol Content and Volatility on Regulated and Unregulated Exhaust Emissions for the Latest-Technology Gasoline Vehicles. Environmental Science & Technology, 41 (11), 4059–4064. 
  • Huai, T., Shah, S.D., Miller, W.J., Younglove, T., Chernich, D.J., Ayala, A. (2006). Analysis of Heavy-Duty Diesel Truck Activity and Emissions Data. Atmospheric Environment, 40(13), 2333–2344. 
  • Huai, T., Durbin, T.D., Younglove, T., Scora, G., Barth M., Norbeck, J.M. (2005) Vehicle Specific Power Approach to Estimating On-Road NH3 Emissions from Light-Duty Vehicles. Environmental Science & Technology, 39(24), 9595-9600. 
  • Huai, T., Shah, S.D., Durbin, T.D., Norbeck, J.M. (2005). Measurements of Operational Activity for Nonroad Diesel Construction Equipment. International Journal of Automotive Technology, 6(4), 333-340. 
  • Huai, T., Durbin, T.D., Miller, J.W., Norbeck, J.M. (2004). Estimates of the Emission Rates of Nitrous Oxide from Light-duty Vehicles Using Different Chassis Dynamometer Test Cycles. Atmospheric Environment, 38(38), 6621-6629. 
  • Huai, T., Durbin, T.D., Miller, J.W., Pisano, J.T., Sauer, C.G., Rhee, S.H., Norbeck, J.M. (2003). Investigation of NH3 Emissions from New Technology Vehicles as a Function of Vehicle Operating Conditions. Environmental Science & Technology, 37(21), 4841-4847. 
  • Huai, T., Durbin, T.D., Shee, S.H., Norbeck, J.M. (2003). Investigation of Emission Rates of Ammonia, Nitrous Oxide and Other Exhaust Compounds from Alternative-Fuel Vehicles Using a Chassis Dynamometer. International Journal of Automotive Technology, 4(1), 9-19.