enforcement of diesel smoke emissions for the state of new jersey

This paper reports on the research program undertaken by the State of New Jersey to determine those tests and instruments which can be used by authorized state agencies for the enforcement of diesel smoke emissions. The state agencies under consideration for the enforcement of diesel smoke emissions are the following: (1) The Division of Motor Vehicles, in its system of state owned inspection stations, will be able to inspect all diesel-powered trucks, and tractors which are registered in New Jersey. (2) The Public Utilities Commission will be able to inspect at their home garages all buses registered in the State. (3) The New Jersey State Police will be able to inspect diesel-powered vehicles on the road. It was decided that the maximum inspection time for each vehicle was not to exceed one minute. On the basis of the one minute per vehicle requirement, eight different tests were evaluated to determine which ones correlated well with normal vehicle operation. These tests included acceleration of a fixed external inertia, free acceleration of only the moving parts of the engine, three ramp tests, a test in which a heavy vehicle was towed, and a driving test in which the vehicle being tested was actually accelerated. The results of tests demonstrated that the modified free acceleration method correlates reasonably well with a loaded steady state cycle, distinguishes the high emitters and is simple to perform. Consequently, the free acceleration test method is recommended for use in inspection stations and on the road. Finally, nearly two hundred vehicles have been tested by this procedure to determine present and potential levels of diesel smoke emissions. Another phase of the program consisted of the determination of smoke measuring techniques and instrumentation. The use and design of smokemeters were extensively investigated, as well as the use of the visual and photographic techniques. Of the various smokemeters tested for this application, several measured smoke satisfactorily in the laboratory, but none were found adequate for field use; they either lacked portability or were unstable due to the deposition of soot on the optics. At the time of writing, specifications for the necessary smokemeter have been drafted and published for bid to interested manufacturers.     

Determination of the Detailed Hydrocarbon Composition and Potential Atmospheric Reactivity of Full-Range Motor Gasolines

The quantitative data obtained with a capillary GLC method, which is used to determine the individual C₃-C₁₂ hydrocarbons in full-range motor gasolines, have been employed in a computer program to calculate the hydrocarbon composition of the vapor in equilibrium with a gasoline at 100°F, as well as the equilibrium vapor-pressure of the gasoline at that temperature. The method used for computation is similar to that previously described by McEwen, assuming the gasoline to behave as an ideal liquid. Also calculated is the potential atmospheric reactivity of this equilibrium vapor relative to that from other gasolines when specific reactivity weighting factors for the individual hydrocarbons are employed. Calculated total vapor-pressure data agree well with experimental Reid vapor-pressure data obtained for typical premium-grade gasolines. Definite differences were observed in the relative potential atmospheric reactivities calculated at 100°F for the equilibrium vapors from the test gasolines.     

National Emission Standards Introduction

A feature of the 63rd annual meeting of the Air Pollution Control Association, held June 14–18, 1970 in St. Louis, was a plenary session on national emission standards. Presided over by John S. Lagarias, APCA past president, the session explored the theme for both motor vehicles and stationary sources through the presentations of Delbert S. Barth and Arthur C. Stern and the discussions of John A. Maga and Robert L. Harris, Jr. The essence of their remarks appears on the following pages.     

The Formulation of Emission Control Strategies Using a Cubic Polynomial Approximation

Assuming the existence of an ambient air standard for a given pollutant, there is some agreement that emission standards for local area and point sources should be established by formulating and testing various “control strategies” with use of a computer diffusion model. The procedure requires several, perhaps many, computer simulations of pollutant dispersion followed by an analysis of the results of each simulation. Part of this analysis is to include an “optimization” of sorts which is intended to provide a workable control strategy which, in turn, is to indicate required emission level reductions for point sources. This paper is intended to describe and apply an approximation technique which, when used in conjunction with a diffusion model, could be of value in determining acceptable emission levels for point sources.     

Determination of Oxides of Nitrogen in Combustion Effluents with a Nitrate Ion Selective Electrode

The nitrate ion selective electrode was investigated as an alternative approach to the present colorimetric determination of nitrate resulting from oxidative absorption of nitrogen oxides from combustion effluents. The electrode offers advantages of speed and relatively simple experimental procedure. Replicate measurements of 10^?4–10^?2M nitric acid solutions using bracketing standards show that the electrode approach is capable of good precision (coefficient of variation = ±4%). Comparison of a method utilizing the nitrate electrode with the more laborious phenol disulfonic acid method for the measurement of nitrogen oxides in both oil and gas fired combustion effluents showed agreement within 4% of the mean even in the presence of high levels of SO₂. The correlation coefficient found for PDS vs nitrate electrode is 0.987.     

An Air Pollution Incident Due to a Stationary Front

In January 1971, the New York City area experienced a period of high pollution in which concentrations exceeded the present criteria for Stage I of the New York City Alert-Warning System. The incident was unusual because the high concentrations were associated with a weak frontal system which moved back and forth over the area and not with a stagnating anticyclone. Concentrations of pollutants were found to be closely related to the movement of the frontal system as well as to changes in wind speed and stability. Climatological criteria for identifying-periods of potential high air pollution and the criteria for mixing heights, transport wind speed and ventilation factors necessary for the issuance of an official advisory from the National Meteorological Center were not met during this incident. Therefore, some re-evaluation and redefinition of these criteria are recommended.     

Honorary Memberships

Honorary Memberships are conferred by the Air Pollution Control Association on persons of widely recognized eminence in some part of the field of air pollution control or who have rendered especially meritorious service to the Association. Honorary Memberships were awarded this year to Dr. Leonard Greenburg and Mr. Milton Reizenstein, both past presidents of APCA.     

Episode control criteria and strategy for carbon monoxide

With respect to health effects and types of emission sources, carbon monoxide is different from SO₂ and airborne participates. The effects of nontoxic CO levels are temporary and reversible. The primary sources are automobiles and trucks, and concentrations are often highly localized. Episode control strategies developed for other pollutants are not applicable for coping with CO episodes.     

Results of Field Measurements of Industrial Particulate Sources and Electrostatic Precipitator Performance

This paper presents results of source size distribution measurements over the size range from 0.1 μm to 5 μm for six classes of particulate sources and fractional efficiency measurements on five full scale electrostatic precipitators and one pilot scale precipitator. The precipitators all showed moderately high to high particulate collection efficiencies for particles having diameters larger than a few micrometers or smaller than a few hundredths of a micrometer and a minimum in collection efficiency for particles having diameters of a few tenths of a micrometer.