This is illustrated by Figure 3, which shows the distribution of emission levels for hydrocarbons, based on the audit of our 1969 and 1970 California production. The broken line shows the actual distribution curve of HC emissions at the end of the production line in 1969. Note that the curve peaks well before the certification standard of 275 ppm, and the sales-weighted average is 177 ppm. This peak shows that most of the cars tested were audited at this smaller emission level. The readings at each end of the curve show that very small numbers of production cars had either very high or very low emission levels.

The solid line shows that the distribution curve for HC emissions in 1970 averaged substantially below the 1969 performance. The 1970 exhaust emission standard, equivalent to 180 ppm, is the vertical dotted line to the left of the 1969 line. The entire performance curve shows the average HC emissions for 1970 improved over 1969 and total emissions were lower, as was the standard. The sales-weighted average for 1970 is 136 ppm.

Similarly, Figure 2 shows the data for CO emissions for the GM car lines for 1969 and 1970. Here again it is apparent that we made real progress in reducing the average emissions from 1970 production below the 1969 level, and, below the standard.

The 1969 sales-weighted average for CO emissions is 1.08 per cent, compared to the standard of 1.5 per cent. For 1970 models, the sales-weighted average dropped to 0.76 per cent, while the standard dropped to 1.0 per cent.

Thus, the total emissions from our 1969 and 1970 California cars added less pollutants to the atmosphere than if they had been exactly at the certification standards. The scattering of emission levels that were on the high end of the emission distribution curves was more than offset by the preponderance of units below the certification standards.

As demonstrated by this production audit data, major reductions have been and are continuing to be made in hydrocarbon and carbon monoxide emissions to the atmosphere. This has been accomplished in spite of the fact that the field performance of some vehicles results in emissions in excess of certification standards. We are trying to improve further on this performance.

In conclusion, let us now turn to the HEW data referred to at the beginning of this statement, said to show that 73 per cent of a group of GM cars "failed" to meet the federal standards. We have already pointed out that classifying percentages of "failures" is not meaningful, that the atmosphere responds to averages. Therefore, if we state the HEW data in terms of sales-weighted averages, the data then show that for all the General Motors cars in their sample the average emissions were as follows:

The source of those figures is shown in figure 3. Thus, according to these data supplied by HEW, General Motors cars are meeting the objective of the Clean Air Act insofar as hydrocarbons are concerned, but do not quite do so with regard to carbon monoxide.

What does that mean as to the effect on the atmosphere? HEW, California, and automobile manufacturers have been using the same series of calculations to determine reduction of pollutants in the atmosphere. This provides a comparison of typical emissions from uncontrolled 1960 models with the later year models which are equipped with control systems. Applying this method of computation to the HEW figures, the average 1968 and 1969 GM car emitted 65 percent less hydrocarbons than the average 1960 model car. Similarly, for carbon monoxide, the average 1968 and 1969 GM car in use shows a reduction of 52 percent. HEW COLD START HC AND CO DATA

More improvement is provided by 1970 model California cars and will be provided by 1971 model cars nationwide. Assuming the same field performance on those 1970 and 1971 cars as the HEW data show for 1968 and 1969 GM models, those later GM cars in use will have average emissions of 87 per cent less hydrocarbons and 68 per cent less carbon monoxide than did the average 1960 model car. These are greater than the reductions set forth in our Annual Report for 1969-namely 80 per cent and 65 per cent respectively.

In this connection, it is of interest that if every one of our 1970 cars were exactly at the standards the total reduction in hydrocarbons from the uncontrolled 1960 cars would be 85 per cent and 71 per cent for carbon monoxide.

When we look at the effect on the atmosphere, instead of "pass-fail" numbers for individual cars, we see that cars in use are limiting emissions very closely to the objectives and expectations which underlie the Clean Air Act and the HEW regulations.

ATTACHMENT B-CHRONOLOGY OF PUBLICATIONS AND EVENTS CONCERNING THE EFFECTS OF LEADED GASOLINE ON EMISSIONS

1957

Hirschler, D. A., Gilbert, L. F., Lamb, F. W., and Niebylski, L. M., "Particulate Lead Compounds in Automobile Exhaust Gas," Ind. Eng. Chem. 49, 1131-1142, 1957. Ethyl publishes classic paper characterizing lead particulate in auto engine exhaust.

1958

U.S. Public Health Service Air Pollution Measurements of the National Air Sampling Network PHS No. 637, 24, 164, 1958. USPHS indicates 3.2% of particulate in Berkeley, California air is lead.

1959

Nebel, G. J., and Bishop, R. W., "Catalytic Oxidation of Automobile Exhaust Gases-an Evaluation of the Houdry Catalyst," presented at the SAE Annual Meeting, Detroit, Michigan, January, 1959. GM researchers show short catalyst life with leaded fuel.

1962

Mueller, P. K., Helwig, H. L., Alcocer, A. E., Gong, W. K., and Jones, E. E., "Concentration of Fine Particles and Lead in Auto Exhaust," presented at Symp. on Advancements in Methods of Air Pollution Meas., Am. Soc. Testing Mat., Los Angeles, Oct. 1962. California Department of Public Health characterizes lead particulate from auto exhaust.

1965

U.S. Department of Health, Education, and Welfare, Public Health Service, Survey of Lead in the Atmosphere of Three Urban Communities, publication No. 999 AP12, Jan. 1965. Three-city study shows atmospheric lead is a measurable source of the body burden of lead.

Cordera, F. J., Foster, H. J., Henderson, B. M., and Woodruff, R. L., “TEL Scavengers in Fuel Affect Engine Performance and Durability," SAE Trans., Vol. 73, 576-608, 1965. Shell researchers show lead scavengers reduce exhaust system durability, but small amounts of lead prevent valve seat wear. Colucci, J. M., and Begeman, C. R., "The Automotive Contribution to Air-Borne Polynuclear Aromatic Hydrocarbons in Detroit,” Air Pollution Control Assoc. Journal, 15, 113, 1965. GM researchers show measurements of lead particulate in the atmosphere correlated with traffic density.

1967

Gagliardi, J. C., "The Effect of Fuel Anti-Knock Compounds and Deposits on Exhaust Emissions," preprint No. 670128, SAE Annual Meeting, January 1967. Ford researchers show exhaust hydrocarbon emissions about 150 ppm higher with leaded fuel than with unleaded.

U.S. Department of Commerce, The Automobile and Air Pollution, report of the Panel on Electrically Powered Vehicles (The "Morse Report"), Oct. 1967. After reviewing entire situation, Morse Committee recommends Federal standards to prevent further increases in lead emitted to the atmosphere. Lawson, S. D., Moore, J. F., and Rather, J. B. Jr., “A Look at Lead Economics in Motor Gasoline," reprint No. 36-67, API Division of Refining, May 1967. Description of the Bonner and Moore study outlining the economics of lead removal from gasoline.

1968

Brodovicz, B. A. “Air Quality Criteria for Pennsylvania," Air Pollution Control Assoc. Journal, 18, 21-23, 1968. The State of Pennsylvania establishes an ambient air quality standard of 5 μg/m3 for lead.

CRC-APRAC organizes working committee to review all existing data on the effect of leaded combustion chamber deposits on exhaust emissions, Feb. 1968. (Committee report in third draft in April, 1970.)

Agnew, W. G., "Science and Technology in Automotive Air Pollution Research," presented to Royal Society of London, Feb. 29, 1968. GM researcher reviews emission problems including effect of lead on catalyst life.

1969

Weaver, E. E., "Effects of Tetraethyl Lead on Catalyst Life and Efficiency in Customer Type Vehicle Operation," Paper No. 690016 presented at SAE International Auto. Engr. Congress, Detroit, Jan. 1969. Ford researchers show lead shorten catalyst life. Gagliardi, J.C., and Ghannam, F. E., "Effects of Tetraethyl Lead Concentration on Exhaust Emissions in Customer Type Vehicle Operation," Paper No. 690015, presented at SAE International Auto. Engr. Congress, Detroit, Jan. 1969. Ford researchers show increased hydrocarbon emissions due to leaded combustion chamber deposits, and poorer lubricant performance with leaded gasoline.

Pahnke, A. J., and Conte, J. F., "Effects of Combustion Chamber Deposits and Driving Conditions on Vehicle Exhaust Emissions," Paper No. 690017, presented at SAE International Auto. Engr. Congress, Detroit, Jan. 1969. Dupont researchers show a small reduction in exhaust hydrocarbon emissions by use of unleaded gasoline.

Hall, C. A., Felt, A. E., and Brown, W. J., "Evaluating Effects of Fuel Factors on Stabilized Exhaust Emission Levels," Paper No. 690014, presented at SAE International Auto. Engr. Congress, Detroit, Jan. 1969. Ethyl researchers show no significant differences in hydrocarbon emissions from leaded and "unleaded prototype" fuels.

Mick, S. H., Discussion at SAE International Auto. Engr. Congress, Detroit, Jan. 1969. GM researchers show direct effect of TEL in increasing hydrocarbon emissions by inhibiting oxidation in exhaust gas.

Schwockert, H. W., "Performance of a Catalytic Converter on Non-Leaded Fuel," preprint No. 690503, SAE Mid-Lear Meeting, Chicago, May, 1969. GM engineer describes good performance of catalyst on non-leaded gasoline.

Agnew, W. G., "Future Emission Controlled Spark Ignition Engines and Their Fuels," presented to API Division of Refining, Chicago, May 12, 1969, and also to SAE St. Louis Section, Oct. 14, 1969. GM researcher reviews gasoline effects on emissions, including lead.

Dr. Lee DuBridge informs automotive company presidents of proposed exhaust particulate goals for 1975 and 1980, Nov. 1969.

1970

Agnew, W. G., "Gasoline Changes Affecting Emission Control," presentation to oil companies, Ethyl Corporation, Dupont, Office of Science and Technology, and HEW at GM Technical Central, January-March, 1970. Also presented to API Marketing Division, Detroit, Feb. 1970, pointing out emissions benefits from unleaded gasoline.

Cole, E. N., "New Engineering Priorities for the 1970s," speech at SAE Annual Meeting indicating emissions benefits from unleaded gasoline, Jan. 14, 1970. Cole, E. N., press release announcing GM 1971 model cars would operate on unleaded (or leaded) 91 octane fuel, Feb. 15, 1970.

Cole, E. N., statement to joint meeting of California Air Resources Board and its Technical Advisory Committee, suggesting 1971 marketing of an unleaded gasoline, March 4, 1970.

Cole, E. N., statement to joint meeting of California Air Resources Board and its Technical Advisory Committee suggesting two grades of gasoline, one with no more than 0.5 g/gal lead, March 5, 1970.

ATTACHMENT C

GENERAL MOTORS CORP.,
Detroit, April 6, 1970.

Hon. ROBERT H. FINCH,

Secretary of Health, Education, and Welfare,
Washington, D.C.

MY DEAR MR. SECRETARY: I appreciate the opportunity of responding to your recent letter asking for General Motors comments on suggested changes in motor vehicles fuels as a means of achieving significant additional reductions in automotive pollutions.

We in General Motors have become increasingly concerned about the detrimental effects of lead on devices designed to develop essentially pollutant-free power systems in the near future. With the issuance of more stringent standards by the State of California for 1972 and 1974 model years and proposed goals by the U.S. Department of Health, Education, and Welfare for 1975 and 1980 models calling for additional reductions in emissions, the need for fuels with reduced or no lead additives became more critical.

Our research indicated that unleaded fuels would reduce the inherent pollutant characteristics of our engine-fuel systems by eliminating the detrimental effects of lead in such areas as spark plug life and lead deposits in combustion chambers. Even more important, however, is the fact that more efficient, long-life emission control systems incorporating such features as manifold reactors, catalytic converters and exhaust gas recirculation systems appear to be technically feasible with unleaded fuel.

This position was expressed in a speech which I gave to the annual meeting of the Society of Automotive Engineers in Detroit January 14, 1970. Shortly thereafter, General Motors held a series of separate meetings with a number of petroleum companies, as well as representatives of the Ethyl Corporation, E. I. duPont, and the Department of Health, Education and Welfare. Our presentation summarized the results of GM research and development work in this area and invited their comments on the technical accuracy of our data. Thus far, no information has been produced which materially varies from the results of our research.

Our research indicated that substantial improvements in emission control could be made by modifications in the engine-fuel relationship. This would involve changes in the composition of fuel, including reduced volatility, removal of light olefins and the elimination of lead additives, as well as possible reductions in compression ratios and other engine modifications necessary to reduce octane requirements.

Earlier this year, on February 15, we announced that all 1971 GM cars are being designed so that the engines will be able to operate satisfactorily on leaded or unleaded gasoline of 91 Research Octane Number (RON).

On March 4 and 5, at the request of Governor Regan, General Motors testified before the California Air Resources Board and its Technical Advisory Board. My statement on March 4 indicated that GM might need unleaded fuels in California to meet that state's 1972 and 1974 emission standards, as well as new federal goals proposed for 1975 models (Attachment No. 1).

Following our testimony on March 4, comments were made by other automobile manufacturers as well as producers of petroleum and lead additives. Testimony by the petroleum companies indicated that some of these firms might have serious difficulties in marketing a completely unleaded 91 RON regular fuel and a leaded 97 RON premium fuel in the immediate future.

As a result of this testimony, General Motors modified its position on the following day, March 5. We indicated our belief that the best solution to the current problem could be accomplished on this basis:

1. Have two grades of fuel from 1972 through 1974 model years with a regular grade at 91 RON with one-half gram of lead per gallon, and a premium grade 97 RON with up to four grams of lead per gallon.

2. Have two grades of fuel for the 1975 model year and beyond. A regular grade of 91 RON with no lead and premium 97 RON with a maximum of four grams of lead per gallon-phasing out lead as improved refinery technology is developed, equipment is replaced, or as the capacity of the petroleum industry to produce unleaded gasoline is expanded. (Highlights of the March 5 statement covering the most important aspects of our recommendations are enclosed as Attachment No. 2.)

Retaining a maximum of one-half gram of lead per gallon of gasoline until the fall of 1974 would reduce the requirements for molecular upgrading by the petroleum companies but would still allow us, in our opinion, to meet 1972 and 1974 California emission standards. Retention of this small amount of lead additives would eliminate concern by some automotive engineers about valve life deterioration in pre-1971 cars if unleaded fuel is used.

It is important that we have unleaded regular fuel by the fall of 1974 because it is anticipated that significant further reduction of auto pollution will require more advanced control systems expected to be ready for introduction by this date and our research indicates that these systems have limited effective life if leaded gasoline is used. Such systems will be necessary, in our opinion, to meet 1975 federal emission goals. However, if a reduction in control system life would