Retrofitting Transit Buses to Reduce Air Emissions Kim Perrotta, Air Quality Coordinator, Ontario Public Health Association CUTA Conference 2003

Why Focus on Transit Buses? Municipalities must lead by example Transit buses can be significant source of air emissions from operations within the control of local government

Emissions by Sector – Region of Waterloo 2001

Vehicle Fleet Emissions – Region of Waterloo 2001

Air Pollutants of Concern Ground-level ozone –Nitrogen oxides (NO x ) –Volatile Organic Compounds Sulphur dioxide (SO 2 ) Carbon Monoxide (CO) Nitrogen Dioxide (NO 2 ) Fine Particulate Matter (PM 10, PM 2.5, PM 1.0 and sulphates)

Fine Particulate Matter Short-term exposures to PM associated with increases in: –Premature deaths –Hospital admissions –Respiratory infections –Asthma symptom OMA attributes 1,900 premature deaths/year to PM

Gaseous Air Pollutants Short-term exposure to gaseous air pollutants also harms health For example, a 1998 study of 11 Canadian cities attributed: –4.1% of NTD to NO 2 –1.4% to SO 2 –0.9% to CO –1.8% to Ozone

Long-term Health Impacts A number of recent long-term studies have demonstrated that poor air quality leads to the development of chronic diseases such as: –Heart disease –Lung cancer –Asthma

Public Health & Diesel Exhaust Significant source of NOx Significant source of PM Contains hundreds of chemicals such as PAHs & Benzene Declared “likely to be carcinogenic to humans” by many organizations

Ultra-Low Sulphur Diesel Sulphur levels of 15 ppm Reduce SOx by about 95% Improves effectiveness of DOC Enables use of DPF & devices that might be used for NOx Region of Waterloo buying ULSD for its Transit Fleet Paying $0.06 more per litre

Oxidation Catalysts & Heavy Duty Diesel Vehicles Diesel Oxidation Catalysts (DOC): –Reduce CO by 40 to 43% –Reduce HC by 43 to 50% –Reduce PM10 by 39 to 50%

Greater Reductions with Older Buses DOC on older Buses ( ): –Reduce CO by about 74% –Reduce THC by about 71% –Reduce PM 10 by about 34% Region of Waterloo will retrofit 86 buses ( ) with DOC Average cost of $3,000/bus.

Repowering Older Buses Repowering & retrofitting buses without electronic controls ( ): –Reduce PM by 92% –Reduce NOx by 33% –Reduce CO 2 by 8% Reduce fuel costs by 8% Costs $20,000-$50,000/bus

Diesel Particulate Filters Diesel Particulate Filters (DPF): –Reduce CO, HC, & PM 10 by additional 78-98% –Reduce PAHs by 70 to 80% –Reduce carbonyls by 90 to 99% Waterloo buying 18 buses equipped with DPF in 2004 Average cost $10,000 to $15,000/bus

Smog Emissions DOC & ULSD & DPF

Smog Emissions – DPF & CNG

Air Toxics: DOC & DPF & CNG