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This page last reviewed June 11 , 2009

Air Pollution Research Reports/Studies - Mobile Sources of Air Pollution

Completed Projects are listed under the following sub-categories:


Catalyst Fuels
Diesel Inspection / Maintenance
Emission Control Off Road
Emission Inventory Toxic Air Contaminants
Emission Monitoring Zero Emission Vehicles

Catalyst

DEMONSTRATION OF A NON-ADDITIVE LEAN- NOx CATALYTIC CONVERTER FOR HEAVY-DUTY DIESEL VEHICLES.  Principal Investigator: Martin J Heimrich. Southwest Research Institute.1996. 92-310

Objectives:  To develop and demonstrate a heavy-duty diesel catalytic converter that is capable of reducing NOx emissions without using additives and which will operate in an oxygen-rich ("lean") environment.

Findings:  The lean NOx catalyst technology investigated was found to be promising, achieving NOx emission reductions of 10 to 20 percent in the laboratory.  However, the technology is not yet ready for installation on a heavy-duty truck.

Importance to ARB’s Program: The results from this project will be used as part of a demonstration of the technological feasibility of a lower NOx emission standard for heavy-duty diesel engines.

DIAGNOSTICS FOR EMISSION CONTROL SYSTEM MALFUNCTION ON THREE-WAY CATALYST EQUIPPED VEHICLES. Energy and Environmental Analysis, Inc. 1985. A2-047-32.

CATALYSTS FOR AUTOMOTIVE POLLUTION CONTROL DEVICES. Principal Investigator: Ken Nobe. University of California, Los Angeles. 1973. 2-009-1A.

Diesel

EVALUATION OF MECHANISMS OF EXHAUST INTRUSION INTO SCHOOL BUSES AND FEASIBLE MITIGATION MEASURES. Principal Investigator: Dennis R. Fitz. University of California, Riverside. 2006. 03-343.

PARTICULATE MATTER MASS MEASUREMENT AND PHYSICAL CHARACTERIZATION - TECHNIQUES AND INSTRUMENTATION FOR LABORATORY SOURCE TESTING. Principal Investigator: Thomas D. Durbin. University of California, Riverside. 2004. 02-334B.

ON-VEHICLE EMISSIONS TESTING SYSTEM. Principal Investigator: David F. May. Analytical Engineering. Inc. 2003. 00-329.

DEMONSTRATION OF DIESEL-FUEL-BORNE CATALYST SYSTEM AND LOW- NOx CONTROL TECHNOLOGY FOR PARTICULATE EMISSIONS.  Principal Investigator: Michael D. Jackson. Acurex Environmental. Co-sponsored with the Southern California Air Quality Management District. 2001. 96-334.

Objectives:  To demonstrate a system that consists of a cerium-based diesel fuel additive and particulate filter, combined with low-NOx engine emission control technology such as cooled exhaust gas recirculation.  Addition of this advanced prototype technology to diesel exhaust systems could assist in the regeneration (restoration and reusability) of particulate filters and in particulate matter (PM) reduction, and would also reduce NOx emissions from heavy-duty diesel engines.

Importance to ARB’s Program: The emergence of new, advanced emission control technology has been a key factor in reducing emissions from motor vehicles over the past 30 years.  Heavy-duty diesel (HDD) engines emit significant quantities of PM and NOx.  A major challenge exists in controlling NOx  and PM emissions from HDD engines simultaneously:   When NOx  emissions are reduced, PM emissions tend to increase and vice versa.  This system has the potential to reduce both PM and NOx  emissions from HDD engines.

DEMONSTRATION OF A FAST-RESPONSE ON-BOARD NOX SENSOR FOR HEAVY-DUTY DIESEL VEHICLES.  Principal Investigator: Jack A. Smith. Southwest Research Institute. 2000. 98-302.

Objectives:   The objectives of this project are to select, calibrate, and demonstrate two types of fast-response sensors capable of providing accurate real-time measurement of exhaust gas oxides of nitrogen (NOx) emissions from on-road, four-stroke cycle, heavy-duty diesel (HDD)-engine-powered vehicles. In order to determine the most appropriate NOx sensors for testing, the contractor will conduct an extensive review of the scientific/technical literature and survey of the most prominent sensor developers and manufacturers of relevant chemical sensing technology. 

Importance to ARB’s Program:   Several control measures contained in California’s 1994 implementation plan for meeting State and federal ozone standards, The California State Implementation Plan for Ozone, call for large reductions in NOx emissions from on-road heavy-duty vehicles.  This project will demonstrate the suitability of the current best available NOx sensor designs for continuously measuring the NOx emissions levels in the exhaust of on-road HDD vehicles, thereby aiding in the design of control strategies for NOx emissions.  It is also expected that subsequent ARB programs or diesel engine manufacturers will use results from this study to adapt a sensor to mass production applications involving closed-loop engine and emission control systems to aid in controlling heavy-duty-vehicle NOx emissions.

DEMONSTRATION OF A HEAVY-DUTY VEHICLE CHASSIS SCREENING TEST FOR COMPLIANCE TESTING HEAVY-DUTY ENGINES.  Principal Investigator: Nigel N. Clark. West Virginia University. 1998. 94-347.

Objectives:  To develop and demonstrate a chassis dynamometer screening test that could be used to test heavy-duty engines (HDEs) for compliance with applicable HDE exhaust emissions standards.  A chassis dynamometer test, which is performed upon the vehicle itself, would be less costly than an engine dynamometer test, which requires removal of the engine from the vehicle.

Findings:  Two heavy-duty truck and engine combinations were tested using a single gear over the entire driving cycle where the vehicle engine speed-versus-time trace is very similar to the engine speed-versus-time trace used in the HDE certification test.  For the test, NOx and particulate matter (PM) emissions were predicted and measured.  The NOx emissions correlated well with those predicted, but only gross PM emitters could be detected with the procedure.  The limited number of test situations means that the viability of the chassis dynamometer screening test as a large-scale compliance tool cannot be assessed until the procedure is applied to a larger number of engine/vehicle combinations.

Importance to ARB’s Program:  More diesel and gasoline heavy-duty engines and vehicles are being fitted with electronic controls and aftertreatment devices (e.g., exhaust gas recirculation or catalytic converters) to control exhaust emissions, and there is now a need to be able to detect system failures that occur in in-use vehicles.  The test developed in this study will be able to act as a screening test for emission certification compliance, and will also have the potential to detect in-use engine/vehicle problems such as failed vehicle speed sensors and low coolant level indicators.  Because chassis emission testing is less expensive than engine dynamometer emission testing, this test offers the potential for screening a greater number of engines.  Engines failing the chassis dynamometer test would be considered for further testing using the heavy-duty vehicle Federal Test Procedure, the official engine certification test (an engine dynamometer test).

HEAVY-DUTY TRUCK POPULATION ACTIVITY AND USAGE PATTERNS.  Principal Investigator: Michael Fischer. Jack Faucett Associates. 1998. 93-306.

Objectives:  To develop contemporary population, activity, and usage pattern data for heavy-duty trucks (HDTs) that operate in California.  Activity data include vehicle miles traveled (VMT), numbers of trips and engine starts, and average speed.  "Usage pattern" refers to range of operation (0-50 miles, 50-200 miles, etc.) and type of use (e.g., delivery, for-hire, construction).  The data were obtained by analyzing existing databases such as California's DMV registration records and national Truck Inventory and Usage Survey data, and by the collection of data by means of on-board dataloggers.

Findings: The total 1995 population of California-registered HDTs was 661,287.  Fifty-nine percent were gasoline-powered and 41% diesel-powered.  The total HDT VMT estimate for calendar year 1992 was 12.3 billion miles, with about 25% attributed to out-of-state HDTs.  The datalogger data for the small fleet of instrumented vehicles indicates that the HDTs in that fleet averaged about 17 trips and 18 starts per day and their average speed was about 30 mph.

Importance to ARB’s Program:   The emissions inventory is used for planning and regulatory purposes and must be as up to date as possible.  The data collected in this study will be used for developing current activity data for HDTs, leading to improvements in this portion of the inventory. The activity data gathered in this study will be used for short-term inventory improvements, such as better characterization of trips, starts, and other activities, and for longer term improvements such as the development of chassis dynamometer driving cycles for HDTs.  Whereas the new analysis is an improvement over previous ones, HDTs are much more difficult to characterize than light-duty vehicles, and the datasets in existence during the study made the task somewhat problematic.  The ARB and DMV are working to reconcile methods and registration datasets for HDTs, and use of data from the International Registration Plan should improve out-of-state HDT characterization for future analyses.  Use of on-board dataloggers should also ease the characterization problem considerably.

FEASIBILITY OF REDUCING NITROGEN OXIDE EMISSIONS FROM HEAVY DUTY VEHICLES.  Principal Investigator: Louis Browning. Acurex Environmental Corp. 1993. A132-085.

Objectives:  To investigate various means of reducing emissions of NOx  and PM from heavy-duty vehicles.  These included diesel and gasoline engine modifications, use of alternative fuels such as alcohols (methanol and ethanol) and gaseous fuels (liquefied petroleum gas and natural gas), and electric and hybrid-electric technologies.

Findings:  The investigator determined that a NOx  emission standard equal to one-half the 1994 standard is feasible for diesel engines by 2002.  For PM emissions the investigator proposed a reduction of approximately 50 percent by 2002 for diesel fueled trucks, and beginning in 1997 for alternatively fueled trucks.

Importance to ARB’s Program:  The results will be used to support low-emission vehicle regulations currently being developed by ARB staff.

HEAVY DUTY DIESEL PARTICULATE TRAP DEMOSTRATION FOR: STATE OF CALIFORNIA-AIR RESOURCES BOARD. Principal Investigator: K Ha. ORTECH Corporation. 1992. 5761 & 98-6001250.

HEAVY DUTY DIESEL VEHICLE INSPECTION AND MAINTENANCE STUDY. Principal Investigator: Christopher S. Weaver, P. E. Radian Corporation, C. A. 1988. A4-151-32.

Volume II

CONTROL OF HEAVY-DUTY DIESEL PARTICULATE EMISSIONS USING CATALYZED CERAMIC TRAPS. Principal Investigator: Terry L. Ullman. Southwest Research Institute, Texas. 1987. A4-132-32.

SURVEY OF HEAVY-DUTY DIESEL ENGINE REBUILDING, RECONDITIONING, AND REMANUFACTURING PRACTICES. Sierra Research, Inc. 1987. A4-152-32.

EFFECT OF DIESEL VEHICLES ON VISIBILITY IN CALIFORNIA. Principal Investigator: John Trijonis. Santa Fe Research Corporation. 1983. A2-072-32.

SURVEY OF HEAVY DUTY DIESEL MAINTENANCE PRACTICES. Principal Investigator: D. F. Hausknecht. Science Applications, Inc. 1981. SAI-068-82-525.

Emission Control

A STUDY OF COMPONENTS INFLUENCING THE DETERIORATION OF VEHICLE EMISSION CONTROL SYSTEMS. Olson Engineering Inc. 1982. A0-104-32.

EVALUATION OF CVS TEST PROCEDURES. Automotive Environmental Systems, Inc. 1976. ARB-4-726.

AUTOMOTIVE EXHAUST EMISSION STANDARDS. TWR Inc. 1974. 3-565.

AN EVALUATION OF THE EFFECTIVENESS OF AUTOMOBILE ENGINE ADJUSTMENTS TO REDUCE EXHAUST EMISSIONS AND AN EVALUATION OF THE TRAINING REQUIRED TO DEVELOP PERSONNEL COMPETENT TO MAKE THE ADJUSTMENTS. Principal Investigator: J. L. Gockel. Clean Air Research Company. 1973. ARB-654.

EVAPORATIVE EMISSION DEVICE RETROFIT STUDY. Principal Investigator: R. G.Gafford, Ph. D. Olson Laboratories, Inc. 1973. ARB-2-1372.

STUDY OF VACUUM SPARK ADVANCE DISCONNECT AS AN NOx CONTROL MEASURE. Automotive Environmental Systems, Inc. 1973. ARB-R-772-73-04 and ARB-2-299-10.

TEMPERATURE TESTING AND ANALYSIS OF THE VACUUM ADVANCE DISCONNECT EXHAUST EMISSION CONTROL. Principal Investigator: R. L. Gibney. Northrop Corporation. 1972. ARB-1086.

TEST AND EVALUATION OF THE AMERICAN POLLUTION CONTROLLED, INC. EXHAUST EMISSION CONTROL DEVICE. Olson Laboratories, Inc. ARB-1902.

Emission Inventory

ASSESSMENT OF OUT OF STATE HEAVY DUTY TRUCK ACTIVITY TRENDS IN CALIFORNIA. Principal Investigator: Nicholas Lutsey. University of California, Davis. 2008. 04-328.

EVALUATION OF ON-ROAD RESULTS FROM A TEST FLEET OF HEAVY-DUTY TRUCKS, PHASE II. Principal Investigator: J. Wayne Miller. University of California, Riverside. 2007. 01-340.

DETERMINATION OF ASBESTOS CONTENT OF CURRENT AUTOMOTIVE DRY FRICTION MATERIALS, AND THE POTENTIAL CONTRIBUTION OF ASBESTOS TO PARTICULATE MATTER DERIVED FROM BRAKE WEAR. Principal Investigator: Stephen Wall, Ph.D. Department of Health Services, CA. 2007. 01-333.

ESTIMATES OF NITROUS OXIDE EMISSIONS FROM MOTOR VEHICLES AND THE EFFECTS OF CATALYST COMPOSITION AND AGING. Principal Investigator: Arthur M. Winer, Ph.D. University of California, LA. 2005. 02-313.

DETERMINATION OF THE CONTRIBUTIONS OF LIGHT DUTY AND HEAVY DUTY VEHICLE EMISSIONS TO AMBIENT PARTICLES IN CALIFORNIA. Principal Investigator:Kimberly A. Prather. University of California, San Diego. 2005. 00-331.

REVIEW AND ANALYSIS OF HEAVY DUTY TRUCK ACTIVITY DATA. Principal Investigator: Wayne Miller. University of California, Riverside. 2005. 03-325.

SUMMARY OF CARB DIESEL-CNG TRANSIT BUS EMISSIONS PROJECT PHASE 1A PANEL MODE (SINGLE DIAMETER) SMPS DATA. Principal Investigator: Britt A. Holmen. University of California, Davis. 2004. 03-309.

VERIFICATION OF SHIP EMISSION ESTIMATES WITH MONITORING MEASUREMENTS TO IMPROVE INVENTORY AND MODELING. Principal Investigator: James J. Corbett, P.E., Ph.D. University of Delaware. 2004. 01-328.

COLLECTION OF EVAPORATIVE EMISSIONS DATA FROM OFF-ROAD EQUIPMENT. Principal Investigator: Dennis McClement. Automotive Testing Laboratories, Inc., Arizona. 2003. 00-315.

INCIDENCE OF MALFUNCTIONS AND TAMPERING IN HEAVY-DUTY DIESEL VEHICLES, PHASE I. Principal Investigator: J.Wayne Miller. University of Riverside, CA. 2003. 01-340.

DETERMINATION OF NON REGISTRATION RATES FOR ON-ROAD VEHICLES IN CALIFORNIA. Principal Investigator: Thomas Durbin. University of Riverside, CA. 2002. 99-318.

HEAVY-DUTY TRUCK EVAPORATIVE EMISSIONS TESTING FOR EMISSIONS INVENTORY. Principal Investigator: Dennis McClement. Automotive Testing Laboratories, Inc. 2002. 98-303.

Objectives:   The objectives of this project are to procure a fleet of at least 10 heavy-duty gasoline trucks (HDGTs) and test them for evaporative emissions.  This project will consist of three main tasks: vehicle selection and procurement, fuel procurement, and evaporative and exhaust emissions testing. 

Importance to ARB’s Program:   As part of continuing efforts to estimate heavy-duty truck emissions as accurately as possible, the ARB needs to obtain data from real HDGTs rather than rely on analytical adjustments to light- and medium-heavy duty truck evaporative emissions data. The evaporative emissions data (diurnal, resting loss, hot soak, and evaporative running loss emissions) from this study will be used to update the ARB’s on-road motor vehicle emissions inventory models.

HEAVY-DUTY VEHICLE FLEET CHARACTERIZATION FOR REDUCTION OF NOx AND PARTICULATE MATTER EMISSIONS IN THE SOUTH COAST AIR BASIN. Principal Investigator: Michael Fischer. Jack Faucett Associates. 2002. 96-317.

Objectives: The objectives of this project are to obtain activity and usage data for all heavy-duty vehicles (HDVs) operating in the South Coast Air Basin (SoCAB), and, based on these data, develop emissions estimates and implementation strategies to accelerate the introduction of low-emitting engines and/or vehicles in the SoCAB.

Importance to ARB’s Program:  The data and conclusions obtained as a result of this study will be used by the ARB to develop and implement control strategies designed to achieve federal ozone standards as they apply to HDVs.  Increased use of low-emitting engines and/or vehicles in the SoCAB, as an alternative to conventional equipment, will also help the ARB meet federal and State air quality standards.

MICROSCALE EMISSIONS MODELING SYSTEM. Principal Investigator: Jeffrey Brian Gerfen. California State Polytechnic University, San Luis Obispo. 2002. 96-316.

Objectives: The objective of this project is to develop equipment and modeling techniques for measuring vehicle activity (e.g., individual vehicle type and its average speed and acceleration) so that emissions can be simulated for a specific roadway type (e.g., freeway).

Importance to ARB’s Program:  The equipment and techniques developed during this study are intended to form the basis for a new generation of emissions models that are designed to calculate emissions for conformity analyses. The emissions that must be estimated are generally for very small regions, thus the term "microscale".  Conformity analyses are required by federal law to ensure that federally funded infrastructure improvement projects do not have an adverse environmental impact. 

TESTING FOR EXHAUST EMISSIONS OF DIESEL POWERED OFF-ROAD ENGINES. Principal Investigator: Mridul Gautam, Ph.D. West Virginia University . 2002. 98-317.

Objective:   The objective of this project is to compile accurate, comprehensive data on off-road diesel engine emissions.  Four off-road equipment diesel engines and appropriate fuel(s) will be procured for emissions testing (fuel will be tested to assure quality control).  A datalogger will be installed in each of the engines to obtain equipment activity estimates, in order to determine the appropriate transient test cycle(s).  Off-road diesel engine emissions testing of the engines will then be performed for oxides of nitrogen, carbon monoxide, carbon dioxide, hydrocarbons, and particulate matter emissions.

Importance to ARB’s Program:   Several areas of California do not currently meet Federal PM standards and the State is under obligation to develop implementation plans for meeting those standards.  PM emissions from off-road diesel engines may be a significant part of the problem.  The 1994 State Implementation Plan for Ozone is the ARB’s roadmap for ensuring that areas attain the air quality standard for ozone by the year 2010.  The ozone SIP requires a more stringent oxides-of-nitrogen standard than the currently adopted 5.8 grams per brake horsepower-hour for diesel-powered off-road engines.  Results from this study will refine the emissions inventory for diesel-powered off-road engine equipment, improving the ARB’s ability to develop effective methods for achieving mandated standards.

DEVELOPMENT OF SOFTWARE FOR SPATIALLY AND TEMPORALLY RESOLVING MOTOR VEHICLE ACTIVITY DATA. Principal Investigator: Yue-Hong Chou. University of California, Riverside. 2000. 98-322.

STUDY TO DEFINE COLD AND HOT START EMISSIONS FINAL INVESTIGATIVE REPORT.  GM Powertrain Division, General Motors Corp. Principal Investigator: Thomas E. Arnold. 1997. 93-322.

Objectives:  To collect data to better characterize start emissions for light-duty autos to be used later to investigate the emissions impacts of vehicle engine starts as a function of "soak" time (the amount of time the engine has had to cool after being fully warmed up), ambient temperature, type of gasoline, and vehicle technology type.

Findings:  Comprehensive analysis of the data from this study and the integration of these data with other start emissions data are currently being performed by the ARB's Mobile Source Control Division.

Importance to ARB’s Program:  The ARB's motor vehicle emission factors and inventories, which are the state's responsibility, are used to support a variety of critical ARB functions and  programs.  Uses include air quality attainment plans, local air pollution control district analysis, conformity analysis, and pollution source problem definition.  Results from this study will be used to support improvement of the ARB's on-road motor vehicle emission factors model EMFAC.

DETERMINATION OF THE EFFECTS OF SPEED, TEMPERATURE, AND FUEL FACTORS ON EXHAUST EMISSIONS.  Principal Investigator: David Chou, P. E. Automotive Testing and Development Services, Inc. 1996. 92-323.

Objectives:  To determine synergistic effects that may occur as cycle speed, ambient temperature, and vehicle fuel (gasoline) are simultaneously varied.  In the typical procedure, only one of these parameters is varied at a time. 

Findings:  Vehicle technology type and vehicle average speed were identified as the factors that most heavily influence exhaust emissions.  Analysis of emissions dependent on fuel type (Phase 1 gasoline vs. Phase 2) revealed statistically significant reductions of 17, 13, and 11 percent respectively for hydrocarbons, carbon monoxide, and NOx .  While temperature had minimal effects on hot stabilized emissions, cold start emissions were higher than hot start emissions.  Interactions among fuel, speed, and temperature were found to be statistically insignificant.  ARB staff are continuing to analyze the data for second-by-second changes in emissions.

Importance to ARB’s Program:  The data from this project will be used to update the emission factors in the ARB's short-term emissions inventory.  In addition, the relationships uncovered will be reflected in improvements to the longer-term model.

ON-BOARD HEAVY-DUTY TRUCK MOBILE EMISSION TESTING IN SUPPORT OF MOBILE SOURCE EMISSION INVENTORIES AND ON BOARD EMISSIONS FACTOR FOR DIESEL BUS. Acurex Environmental Corporation, C.A. 1996. 92-924.

MONITORING OF PERSONAL DRIVING HABITS AND VEHICLE ACTIVITY. Principal Investigator: Alan Arena. Automotive Testing and Development Services, Inc. 1995. A132-175.

Objectives:  To collect activity data (for example, vehicle speeds, numbers and durations of trips, catalyst temperatures) for light-duty vehicles loaned by private citizens to the ARB for in-use surveillance testing. 

Findings:  The results of this study indicate that light-duty autos make significantly more trips per day than had been estimated before the study was undertaken: about 7 trips versus the estimated 3.  Additional data gathered showed the average trip length to be 7.4 miles and about 14 minutes in length.  The vehicles in this study traveled an average of 49 miles per day. 

Importance to ARB’s Program:  The data will be used to improve the vehicle activity estimates used in the ARB's EMFAC/BURDEN emissions inventory models.

ON-ROAD MOTOR VEHICLE ACTIVITY DATA.  Principal Investigator: Yuji Horie, Ph.D. Valley Research Corporation. 1994. A132-182.

Objectives:  To update and upgrade several segments of the database used to calculate the ARB's on-road motor vehicle emissions inventory.

Findings:  Several segments of the database used to calculate the Air Resources Board's mobile source emissions inventory were improved:  (1) vehicle registration by model and year, by county; (2) mileage accumulation rates for vehicles; and (3) urban bus vehicle miles traveled, by speed.

Importance to ARB’s Program:  The ARB is required by the Health and Safety Code to inventory sources of air pollution.  The results of this study will be used to develop and maintain more current motor vehicle emissions inventories. 

TASK ORDER CONTRACT FOR EMISSIONS INVENTORY PROJECTS. Principal Investigator: Frank Di Genova & S Kingsley Macomber. Sierra Research Inc. 1994. A096-214 & SR-94-01-01.

VEHICLE LOCATION SYSTEMS. Principal Investigator: Frank Di Genova. Sierra Research, Inc. 1994. A096-214 & SR-94-01-03.

CHARACTERIZATION OF DRIVING PATTERNS AND EMISSIONS FROM LIGHT-DUTY VEHICLES IN CALIFORNIA.  Principal Investigator: Thomas C. Austin. Sierra Research.1993. A932-185.

Objectives:  To develop a model to estimate vehicle emissions based on a given driving cycle and to develop a driving cycle more representative of current California driving conditions.

Findings:  Using models developed by the contractor, the new driving cycle reveals that light-duty vehicles produce double the emissions of CO and NOx  than expected from the Federal Test Procedure (FTP).  HC emissions remained nearly the same. 

Importance to ARB’s Program:  This cycle is undergoing testing and analysis to determine its suitability as a possible supplement to the FTP.

QUANTIFICATION OF EVAPORATIVE RUNNING LOSSES FROM LIGHT DUTY GASOLINE POWERED TRUCKS. Principal Investigator: Dennis McClement. Automotive Testing Laboratories, Inc. 1992. A992-224.

QUANTIFICATION OF EVAPORATIVE RUNNING LOSS EMISSIONS FROM GASOLINE-POWERED PASSENGER CARS IN CALIFORNIA.  Principal Investigator: Dennis Mc. Clement. Automotive Testing Laboratories. 1991. A832-153.

Objectives:  To gather data on evaporative running loss emissions from passenger cars.

Findings:  The test results typically showed relatively low emissions, but some vehicle/temperature/fuel-volatility conditions produced substantially higher running loss emissions.  Slow-speed driving conditions produced increased emissions from most vehicles. 

Importance to ARB’s Program:  These findings have been used to update and improve the on-road motor vehicle emissions inventory.  This study also contributed to the recognition of the need to include running losses in the ARB's evaporative emissions test procedure, which has subsequently been updated. 

DEVELOPMENT OF THE CALIMFAC California I/M Benefits Model. Sierra Research Inc. 1990. A6-173-64.

A STUDY OF MULTI-DAY STORAGE PATTERNS FOR GASOLINE-FUELED VEHICLES IN THE SOUTH COAST AIR BASIN. Principal Investigator: Yuji Horie Ph.D. Valley Research Corporation. 1989. A6-196-32.

CHARACTERIZATION OF EXHAUST EMISSIONS FROM TRAP-EQUIPPED LIGHT-DUTY DIESELS. Principal Investigator: Lawrence R. Smith. Southwest Research Institute. 1989. A5-159-32.

RUNNING LOSS EVAPORATIVE EMISSIONS DETERMINATION BY THE POINT SOURCE METHOD. National Institute for Petroleum and Energy Research, Oklahoma.1989. A732-151.

Objectives:  To quantify evaporative running losses from two light-duty vehicles -- a carbureted 1987 Chevrolet, and a fuel-injected 1985 Buick -- by measuring evaporative emissions at specific locations on the vehicles.

Findings:  The test results showed that the charcoal canister of the evaporative emission control system is the major source of evaporative running losses and that, for the carbureted vehicle, evaporative running loss emissions are as high as tailpipe hydrocarbon emissions.  The carbureted vehicle showed significantly greater running loss emissions than did the fuel-injected vehicle.

Importance to ARB’s Program:  The findings contributed to an ARB study to develop an emissions database and emission factors for evaporative running losses.

ASSESSMENT OF HEAVY-DUTY GASOLINE AND DIESEL VEHICLES IN CALIFORNIA: POPULATION AND USE PATTERNS. Principal Investigator: Yuji Horie. Pacific Environmental Services, Inc. 1985. A2-155-32.

CALIFORNIA UTILITY EQUIPMENT USE SURVEY 1981-1982 DATA BOOK. CIC Research, Inc. 1983. A0-102-32.

STUDY OF EMISSIONS IMPACT OF SELECTED AFTERMARKET PARTS. Custom Engineering, Inc. 1983. A0-138-32.

CHARACTERISTICS AND IMPACT OF ELECTRONIC AUTOMOTIVE EMISSION CONTROL SYSTEMS. Principal Investigator: Richard R. Carlson. System Control Inc. 1982. A0-144-32.

A STUDY OF DRIVING AND STORAGE PATTERNS OF NONPRIMARY PRIVATE VEHICLES IN THE SOUTH COAST AIR BASIN. Principal Investigator: Yuji Horie. Pacific Environmental Services, Inc. 1981. A0-073-31.

A HEAVY DUTY VEHICLE EMISSION INVENTORY SYSTEM. Principal Investigator: Kenneth W. Ariedge. TRW Environmental Engineering Division, C.A. 1978. A6-051-87.

A MOBILE SOURCE EMISSION INVENTORY SYSTEM FOR LIGHT DUTY VEHICLES IN THE SOUTH COAST AIR BASIN. Principal Investigator: H. S. Goodman. TWR Environmental Engineering Division. 1977. ARB-4-1236.

MOBILE SOURCE EMISSION INVENTORY. Olson Laboratories Inc. 1977. ARB-4-956 & ARB-5-434.

DEGRADATION EFFECTS ON MOTOR VEHICLE EXHAUST EMISSION. Principal Investigator: E. J. Norman. Olson Laboratories, Inc. 1976. ARB-3-199 & ARB-3-584.

EXPLOR (EXAMINATION OF POLLUTION LEVELS OF ROADWAYS). Principal Investigator: J. W. Kirsch. Systems, Science and Software. 1974. ARB-659.

Emission Monitoring

EVALUATION OF THE PROPOSED NEW EUROPEAN METHODOLOGY FOR DETERMINATION OF PARTICLE NUMBER EMISSIONS AND ITS POTENTIAL IN CALIFORNIA FOR IN USE SCREENING. Principal Investigator: Dr. Thomas D.Durbin. University of California, Riverside. 2008. 05-320.

MEASUREMENT ALLOWANCE PROJECT-ON-ROAD VALIDATION. Principal Investigator: J. WAYNE MILLER. University of California, Riverside. 2008. 03-345.

EVALUATIONN OF PORTABLE EMISSIONS MEASUREMENT SYSTEMS (PEMS) FOR INVENTORY PURPOSES AND THE NOT-TO-EXCEED HEAVY-DUTY DIESEL ENGINE REGULATION. Principal Investigator: J. WAYNE MILLER. University of California, Riverside. 2006. 03-345.

INCORPORATION OF RADIO TRANSPONDERS INTO VEHICULAR ON-BOARD DIAGNOSTIC SYSTEMS. Principal Investigator: Frank Di Genova. Sierra Research, Inc. 2000. 96-332.

Objectives:  The objective of this study is to develop an on-board transponder system for reporting emissions system failures.

Importance to ARB’s Program:  Successful development and application of this automatic reporting system would reduce vehicle inspection costs for drivers and ensure detection of vehicles with emissions system failures.  The results and options provided by this study will offer ARB policymakers a selection of measures and/or programs that could be used to improve the effectiveness of the Smog Check program.

CHARACTERIZATION OF PARTICULATE EMISSIONS FROM GASOLINE-FUELED VEHICLES. Principal Investigator: Joseph M. Norbeck. University of California, Riverside. 1998. 94-319.

Objectives:  To provide current inventory data for particulate emissions from gasoline-powered vehicles.  Emissions from light-duty automobiles will be analyzed for mass and particle size distribution, and chemical speciation will be performed on samples of total particulate matter.

Importance to ARB’s Program:  The data from this study will be made available for improving the ARB's particulate matter emissions inventory and for use in future state implementation plans for attainment of the national ambient air quality standard for particulate matter.

ON ROAD CO REMOTE SENSING IN THE LOS ANGELES BASIN. Principal Investigator: Donald H. Stedman. University of Denver, C. O. 1991. A932-189.

DEVELOPMENT OF AN ANALYZER FOR EXHAUST FROM METHANOL / HYDROCARBON FUELED MOTOR VEHICLES. Principal Investigator: Derhsing Luu. Global Geochemistry Corporation. 1987. A4-150-32.

MOTOR VEHICLE SAMPLING EXPERIMENT. Principal Investigator: L. Willard Richards. Rockwell International, C.A. 1977. ARB-3-986 & ARB-4-335.

Fuels

REFINEMENT OF SELECTED FUEL CYCLE EMISSIONS ANALYSES. Principal Investigator: Stefan Unnasch. Arthur D. Little, Inc. 2001. 98-338.

IMPACT OF REFORMULATED FUELS ON PARTICLE- AND GAS-PHASE EMISSIONS FROM MOTOR VEHICLES.  Principal Investigator: Thomas W. Kirchstetter & Robert A. Harley. University of California, Berkeley. 1999. 95-330.

Objectives:  To measure gaseous and particulate emissions from in-use motor vehicles operating under specific conditions in the Caldecott Tunnel east of Oakland.  The results will be used, along with those of studies performed in the tunnel in 1994 and 1995, to determine the effects of cleaner burning gasoline on the amounts of ozone and particulate precursors emitted from motor vehicles.

Importance to ARB’s Program: An evaluation of actual benefits is needed for determination of the success of the cleaner burning gasoline program.  Better understanding of particulate matter emitted from motor vehicles will provide for more cost-effective programs for reducing exposure to unhealthy levels of PM10 and PM2.5.

DETERMINATION OF USAGE PATTERNS AND EMISSIONS FOR PROPANE / LPG IN CALIFORNIA. Principal Investigator: Michael Sullivan. Freeman, Sullivan & Co. 1992. A032-092.

A STUDY OF EXCESS MOTOR VEHICLE EMISSIONS CAUSES AND CONTROL. Sierra Research Inc. 1988. A5-188-32.

CHEMICAL CHARACTERIZATION OF AUTOMOBILE FUELS AND EXHAUST EMISSIONS AND EXAMINATION OF THE COMPOSITIONAL CHANGES IN EXHAUST INTRODUCED BY FUEL AND ENGINE DESIGN VARIATIONS. Principal Investigator: Prof. Melvin Calvin. University of California, Berkeley. 1973. ARB-5-066-1.

Inspection / Maintenance

EVALUATION OF TECHNOLOGY TO SUPPORT A HEAVY DUTY DIESEL VEHICLE INSPECTION AND MAINTENANCE PROGRAM. Principal Investigator: Nigel N. Clark. West Virginia University, WV. 1998. 98-319.

PERFORMANCE OF ANALYSIS AND RESEARCH TASK FOR THE CALIFORNIA SMOG CHECK PROGRAM. Sierra Research Inc. 1994. A164-074.

A STUDY OF EMISSIONS DETERIORATION, POST - I / M TAMPERING, AND COST / EFFECTIVENESS OF THE SMOG CHECK PROGRAM. Principal Investigator: Thomas C. Austin. Sierra Research Inc. 1990. A6-220-64.

VEHICLE EMISSION INSPECTION AND MAINTENANCE STUDY. Principal Investigator: E. J. Norman. Northrop Corporation. 1971. ARB-1522.

Off - Road

CHARACTERIZATION OF THE OFF-ROAD EQUIPMENT POPULATION. Principal Investigator: Rick Baker. Eastern Research Group, Inc.2008. 04-315.

EMISSION CONTROL TECHNOLOGIES FOR OCEAN GOING VESSELS (OGVs). Principal Investigator: Hamid Hefazi, PhD. California State University, Long Beach. 2008. 06-327.

THE DEVELOPMENT OF EXHAUST SPECIATION PROFILES FOR COMMERCIAL JET ENGINES. Principal Investigator: Philip D. Whitefield. University of Missouri - Rolla. 2007. 04-344.

MONITORING AND MODELING OF ULTRAFINE PARTICLES AND BLACK CARBON AT THE LOS ANGELES INTERNATIONAL AIRPORT. Principal Investigator: John Froines. University of California, Los Angeles. 2007. 04-325& 05-324.

THREE-WAY CATALYST TECHNOLOGY FOR OFF-ROAD EQUIPMENT POWERED BY GASOLINE AND LPG ENGINES.  Principal Investigator: Jeff J. White. Southwest Research Institute. 1999. 95-340.

Objectives: The objective of this project is to develop and evaluate two emissions control technologies for off-road gasoline and liquefied petroleum gas (LPG) industrial equipment engines of 25 to 175 horsepower.  Existing off-road engine test procedures and cycles will be further developed and the investigators will suggest emissions standards for off-road gasoline and LPG engines.

Importance to ARB’s Program: The development of these emissions control technologies and improvement of existing testing protocols will help the ARB establish emissions standards that will effectively limit industrial equipment emissions.  Adequate control technologies will also assist the ARB in achieving the emissions reductions necessary to meet Federal ozone standard, as projected by California's implementation plan. Use of these new emissions control technologies by industry will assist the ARB in reducing total hydrocarbons, non-methane hydrocarbons, carbon monoxide, and oxides of nitrogen from off-road engine emissions.

RECREATIONAL BOATING ACTIVITY TRENDS IN CALIFORNIA 1995-2020. Principal Investigator: Michael J. Potepan. San Francisco State University. 1997. 95-721.

ASSESSMENT OF THE EFFECTS OF PROPOSED LOCOMOTIVE REGULATIONS ON GOODS TRANSPORT MODES AND LOCOMOTIVE EMISSIONS. Principal Investigator: Judith Lamare, Ph.D. Jack Faucett Associates, Inc. 1996. 92-930.

DEVELOPMENT OF AN IMPROVED INVENTORY OF EMISSIONS FROM PLEASURE CRAFT IN CALIFORNIA. Principal Investigator: Marianne Causley. Systems Applications International.  1995. A132-184.

Objectives:  To develop an improved emissions inventory for pleasure craft operations in California.  The existing inventory was based on incomplete and now outdated data from a 1973 study.  The investigators for this study conducted a survey of pleasure craft owners statewide.  The results were combined with emission estimates for Coast Guard-documented vessels and emissions estimated for rental vessels.

Findings:  Nearly all boating activity in California occurs on Saturdays and Sundays during the period April through September.  The heaviest time of use is around noon.  Average annual fuel consumption in this study was 77.5 gallons, about half that of an earlier ARB estimate. NOx , total organic gases (TOG), and sulfur oxides SOx  emissions had decreased by about 45, 18, and 85 percent, respectively, compared to the 1973 inventory.  CO had increased by about 3 percent and PM 100 percent.  One of the reasons for the changes in values was that emission factors have been updated since the earlier inventory.  Other causes may include overestimation of fuel consumption in the earlier estimate and the relatively low level of California's water reservoirs during the period 1993-1994, when hours of pleasure craft operation were reduced.

Importance to ARB’s Program:  The ARB is required by the Health and Safety Code to inventory sources of air pollution.  The inventory completed in this study will provide updated data for use by the ARB in estimating emissions from pleasure craft.  The procedures for calculating pleasure craft emissions will be reviewed and improved as necessary.

CONTROLLING LOCOMOTIVE EMISSIONS IN CALIFORNIA.  Principal Investigator: Christopher S. Weaver. Engine, Fuel, and Emissions Engineering, Inc.1995. A032-169 & 92-917

Objectives:  To identify feasible and cost-effective measures to reduce locomotive emissions, develop and recommend a regulatory strategy and implementation schedule for controlling locomotive emissions, and identify and recommend areas for further research, development, and demonstration.

Findings:  The following methods of reducing locomotive emissions were identified:  diesel engine and diesel fuel modifications, selective catalytic reduction (SCR) of diesel emissions, use of alternative fuels such as liquefied natural gas, and locomotive electrification.  A regulatory strategy that focuses on oxides of nitrogen and particulate matter emissions was proposed.  Research was recommended to develop a suitable short, in-the-field emission test procedure, and a demonstration project is recommended for SCR technology.

Importance to ARB’s Program:  This report currently forms the basis for ongoing locomotive regulatory development by ARB staff.  These regulations are expected to be presented to the Board in 1994.

A STUDY TO DEVELOP PROJECTED ACTIVITY FOR "NON ROAD MOBILE" CATEGORIES IN CALIFORNIA, 1970-2020. Principal Investigator: Anil K. Puri. Ph.D. California State University, Fullerton. 1994. 92-732.

DEVELOPMENT OF BASELINE AND CONTROLLED EXHAUST EMISSION RATES FOR OFF-HIGHWAY VEHICLE ENGINES. Principal Investigator: Jeff. J. White. Southwest Research Institute, Texas. 1993. A198-076.

STUDY OF VISIBLE EMISSIONS FROM SHIPS WITH STEAM BOILERS. Principal Investigator: A. Walter Wyss. Acurex Corporation. 1982. A9-121-30.

INVENTORY OF EMISSIONS FROM MARINE OPERATIONS WITHIN THE CALIFORNIA COASTAL WATERS. Principal Investigator: W. C. Kelly. Scott Environmental Technology, Inc. 1981. A6-208-30.

INVENTORY OF EMISSIONS FROM BOATING SOURCES IN CALIFORNIA. Principal Investigator: N. R. Parker. KVB. Inc. 1980. A8-138-31.

Toxic Air Contaminants

INTERNAL COMBUSTION ENGINE (ICE) AIR TOXIC EMISSIONS. Principal Investigator: Xiaona Zhu. University of California, Riverside. 2004. 02-334A.

RECLAMATION OF AUTOMOTIVE BATTERIES: ASSESSMENT OF HEALTH IMPACTS AND RECYCLING TECHNOLOGY. Principal Investigator: Michelle Montano. Acurex Environmental Corporation.1999. 93-323.

Objectives:  To evaluate the health and hazard impacts of recycling and disposing of spent batteries used to power electric vehicles (EVs).  Investigators evaluated lead-acid, nickel-cadmium, nickel-metal hydride, sodium sulfur, sodium-nickel chloride, lithium-iron sulfide and disulfide, lithium-polymer, lithium-ion, and zinc-air batteries.  

Findings: This study (Task 2 of the original proposal) compared the relative health impacts of recycling EV batteries, in terms of cancer, toxicity, and ecotoxicological potential, as well as leachability, flammability, and corrosivity/reactivity hazards. The analysis does not represent an absolute impact assessment and recycling processes were not compared to other sources of environmental pollution. Results seem to indicate that lead-acid batteries processed by smelting operations have a larger potential negative health impact than the same batteries processed by other means or other battery types handled by the same process.  The sodium-nickel chloride batteries also rank relatively more toxic.  On an overall basis, the more advanced batteries, such as nickel-metal hydride, lithium-polymer, and lithium-ion, represent a great improvement over conventional lead-acid battery technology, both in terms of performance and impacts from recycling the spent batteries.

NOTE: There is a great deal of uncertainty surrounding this analysis.  Battery constituents are reasonably well known, but they vary somewhat with battery manufacturer and are likely to change as battery development progresses.  Recycling technologies for many of these batteries are in their infancy.  In some cases, actual emissions have been measured, while in others, engineering judgment has been applied to adapt emissions factors from other presumably similar processes.  In addition, there is substantial uncertainty surrounding the health impact values (cancer potency factors, maximum contaminant levels, etc.). Because of these uncertainties, interpretations made from this analysis should be viewed with caution.

Importance to ARB’s Program: The ARB expects that all zero-emissions vehicles will initially be EVs.  The vast majority of the batteries used to power these vehicles contain substances that are toxic and may pose a health hazard to humans and the environment. This data will make it possible to identify and assess the potential fate of spent batteries prior to market penetration, especially toxic/hazardous components of the new battery technologies.

DEVELOPMENT OF INTEGRATED BIOASSAY AND CHEMICAL METHODS TO CHARACTERIZE HEAVY- DUTY DIESEL EXHAUST. Principal Investigator: Dennis P. H. Hsieh. University of California, Davis. 1998. 92-342 & 94-335

EVALUATION OF FACTORS THAT AFFECT DIESEL EXHAUST TOXICITY.  Principal Investigator: Dr. Joseph M. Norbeck. University of California, Riverside. 1998. 94-312.

Objectives:   To perform a preliminary assessment of the potential impact of diesel fuel formulation on the speciation and toxic components of diesel exhaust.  A heavy-duty diesel engine was operated over a standard test cycle using three fuels: a pre-1993 diesel fuel, a low aromatic diesel fuel, and a post-1993 fuel with higher aromatic content.

Findings: A major part of this study involved analysis for polycyclic aromatic hydrocarbons (PAHs) and their derivatives.  For volatile PAHs, the concentrations in the exhaust appear to be derived mainly from the PAH initially present in the fuel.  In contrast, the emission levels of most of the less volatile PAHs were similar for all fuel types, suggesting that these PAHs are mainly formed during combustion.  Levels of particle-associated nitro-PAHs were similar for all fuels.

Importance to ARB’s Program: The ARB is evaluating diesel exhaust for possible identification as a toxic air contaminant.  Diesel exhaust is a complex mixture of many individual chemicals, and its composition has probably changed since the ARB's 1993 diesel fuel reformulation regulation.  Although differences were found, in general, the exhaust does not show substantial compositional changes.

FORMALDEHYDE EMISSION CONTROL TECHNOLOGY FOR METHANOL FUELED VEHICLES.   Principal Investigator: Matthew S Newkirk. Southwest Research Institute.1994. A732-148.

Objectives:  To identify and demonstrate durable emission control systems capable of reducing formaldehyde emissions from methanol-fueled vehicles to levels comparable to those from gasoline-fueled vehicles while not adversely affecting other criteria pollutant levels.

Findings: Eighteen catalyst systems were evaluated.  Of these, one was selected and installed on each of four vehicles for a 4,000-mile durability test.  The test fleet generally exhibited low emission levels (including those for formaldehyde), but the investigator cautioned that it should be remembered that a vehicle with only 4,000 miles of use is essentially a new vehicle and would be expected to exhibit low emission levels. 

Importance to ARB’s Program:  These findings will be used to demonstrate that formaldehyde emissions from methanol-fueled vehicles can be reduced to about the same level as those for gasoline-fueled vehicles; thus use of methanol has the potential for achieving substantial air quality benefits.

MEASUREMENT AND CHEMICAL CHARACTERIZATION OF VAPOR-PHASE MUTAGENS IN DIESEL EXHAUST. Principal Investigator: Dennis P. H. Hsieh. University of California, Davis.1993. A032-095.

Objectives: To use microbial tests (bioassays) to help direct chemical analyses of diesel exhaust, a complex emissions mixture, in order to chemically identify vapor-phase mutagenic air contaminants.

Findings: Methods were developed to collect and concentrate vapor-phase organic compounds. The methods were then integrated with a modified bioassay for vapor-phase mutagens. The mutagenic activity of the vapor phase was found to be comparable to that of the particle phase.

Importance to ARB’s Program: Diesel exhaust is a candidate toxic air contaminant. As a result of this research, ARB now has important information regarding the health benefits that may result from regulatory controls on diesel engine exhaust such as may be implemented under the TAC control program.

CONTROL OF BENZENE EMISSIONS FROM LIGHT - DUTY MOTOR VEHICLES. Principal Investigator: Martin J. Heimrich. Department of Emissions Research. 1991. A6-204-32.

MEASUREMENT OF TOXIC EXHAUST EMISSIONS FROM GASOLINE POWERED LIGHT - DUTY VEHICLES. Principal Investigator: Mary Ann Warner Selph. Southwest Research Institute, Houston. 1989. A6-198-32.

GENOTOXICITY OF DIESEL EXHAUST PARTICLES AND VAPORS COLLECTED FROM ENGINES WITH AND WITHOUT PARTICULATE TRAP OXIDIZERS. Principal Investigator: Ronald E. Rasmussen Ph. D. University of California, Irvine. 1988. A5-130-33.

Zero Emission Vehicles

VEHICLE-TO-GRID DEMONSTRATION PROJECT: GRID REGULATION ANCILLARY SERVICE WITH A BATTERY ELECTRIC VEHICLE. Principal Investigator: Alec N. Brooks. AC Propulsion, Inc. 2002. 01-313.

AUTOMOTIVE CHARGING SYSTEM FOR ELECTRIC VEHICLES: DEMONSTRATION PROJECT.  Bevilacqua-Knight, Incorporated; Co-sponsored with the Southern California Air Quality Management District. 2000. 96-321.

Objectives: The objectives of this project are to design, fabricate, test, and demonstrate a reasonably priced electric vehicle (EV) automatic charging system that will only require the EV driver to provide an actuation signal in order to charge the vehicle batteries.

Importance to ARB’s Program:  This technology will help reduce emissions from vehicles by improving the market appeal of EVs and speeding the introduction of EVs into California's automobile population.

STUDY OF THE SECONDARY BENEFITS OF THE ZERO-EMISSION VEHICLE PROGRAM. Principal Investigator: A.F. Burke. University of California, Davis. 2000. 99-328.

EVALUATION OF FUEL-CELL REFORMER EMISSIONS.  Acurex Environmental. Principal Investigator: Mr. Stephan Unnasch. Arcadis Geraghty & Miller Inc. 1999. 95-313.

Objectives:  The objectives of this project are to evaluate fuel-cell reformer technology (the fuel-cell reformer changes the fuel in such a way that hydrogen is released for use by the fuel cell) and to characterize and quantify the emissions that may result from fuel-cell vehicles.

Importance to ARB’s Program:  Results from this project will help the ARB assess the role of fuel-cell technology in reducing emissions from vehicles.

EVALUATION OF FUEL-CYCLE EMISSIONS ON A REACTIVITY BASIS. Acurex Environmental Corporation. 1996. A166-134.

Volume I:

Volume II:

DEVELOPMENT OF AN OFF-HIGHWAY MOBILE SOURCE EMISSIONS MODEL. Energy and Environmental Analysis, Inc.1995. A132-164.

Objectives:  To develop an off-road mobile source emission model similar to the EMFAC/BURDEN on-road motor vehicle inventory models. 

Findings:  The off-road model developed will be able to calculate emissions inventories for 12 different classes of off-road equipment, including construction and mining equipment, agricultural equipment, and lawn and garden equipment.  The model will ultimately replace the current piecemeal methods used to calculate off-road emissions inventories.

Importance to ARB’s Program:  This model is designed to complement and supplement the categories in the ARB's Emission Data System.

1992 ELECTRIC VEHICLE TECHNOLOGY AND EMISSIONS UPDATE. Principal Investigator: William Hamilton. Systems Applications, Inc. 1992. A866-187.

Sections of this book:
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Atmospheric Processes
Climate Change
Ecological Effects of Air Pollution
Economic Studies
General
Health Effects of Air Pollution
ICAT Grant Program
Indoor Air Quality
Mobile Sources of Air Pollution
Stationary Sources of Air Pollution

Past Air Pollution Research

 
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