DISCUSSION

E. K. von Brand. This is in regard to the instrumentation needed to take all the corrective steps indicated by previous speakers. One type of instrument is called a tape-recording smokemeter or exhaust pattern recorder, and it can help to clear the air when used for optimizing the adjustment of fuel-burning equipment, particularly the automotive engine. The American Petroleum Institute and the Society of Automotive Engineers have investigated this equipment for a good many years now. And many people are taking advantage of it, especially abroad. Even in Japan, they have tried it. This gas sampler is operated as a rule with fully continuous tape motion, but can also be set up as sequential sampler with repeat cycle timer. While widely used for diesel work, it is even more helpful for checking the adjustment of gasoline engines. Exhaust records made with this recorder show that most gasoline engines are poorly adjusted, smokewise and emissionwise. This fact is not known to operators or servicemen because the exhaust looks clear to the unaided eye. This is true for old engines and very much so for new engines, too, as I know from personal experience. In the stop-andgo driving in urban areas, where engines idle a good deal of the time, better adjustment is very helpful in reducing air pollution. Adjusted for clean-aspossible within the limits of design, no matter how poor the equipment, an engine can still be made to perform up to its best ability. Better combustion will sustain good engine performance, and reduce maintenance costs; deposit formation is retarded; oil stays cleaner longer; spark life is longer, and that means satisfactory spark life. In case the engine is in poor condition in some respects, a continuous exhaust record from this recorder in connection with other instruments, and very often by itself, provides a means of diagnosis of ring wear, oil pumping, and oil choke; it's not a mere smokemeter; it's an exhaust pattern recorder. Because of overrich mixture from excess fuel supply, automatic chokes are particularly bad. In a high percentage of tests it has been found, with a tape speed of 4 inches per minute, that the exhaust clears up in 2 or 3 minutes, as it should; then all of a sudden, after another minute or two, a very dirty, gray smoke is produced. However, the exhaust looks clear. Nobody knows. Air pollution goes on. Nonparticulate emissions are also important. Studies by numerous authorities show that the gasoline engine, rather than the diesel, is the main producer of toxic

gases. The development of sensitized tape might increase the possibilities of this recorder. However, just as it is, it can be used even for nonparticulate matter, provided a useful correlation is established between the presence of the toxic gas and particulate emissions-foreign particles, fumes, oil, etc. This possibility should be more fully explored by investigators with the proper facilities.

Christopher R. Landmann. In another session, Dr. Wynder of the Sloan-Kettering Institute mentioned medical effects on mice in studies seeking to differentiate the various pollutants. He found emissions of diesel engines less toxic and less cancerproducing than emissions of gasoline engines. I would like Professor Meyer to comment, particularly on quantitative differences in the effects of emissions from diesel and gasoline engines.

Meyer. I don't think I'm qualified to discuss the problem of cancer-producing characteristics of various constituents of exhausts from either gasoline or diesel engines. In my opinion, these matters are largely yet to be explored. We are not certain whether smears on the skin of mice relate properly to the lung cancer incidence. So it is a little early to speculate on whether the diesel engine or the gasoline engine is the more serious offender. I do know that in Europe the concern has been primarily with the diesel engine. In this country we have been looking more at the gasoline engines. simply because we have so many more of them. But I believe it is too early to make numerical comparisons.

I

G. C. Hass. In Dr. Chambers' paper, he includes an estimate that the current California hydrocarbon standard may accomplish only a 40-percent reduction of total emissions if applied to all vehicles. believe the present test procedure adopted by the Motor Vehicle Board does take into account the warmup factor which Dr. Chambers feared would reduce the overall effect of control. Also, two recent surveys of the present level of motor vehicle emission would also serve to support the slightly more optimistic contention that the total reduction would be on the order of 60 percent to 70 percent rather than 40 percent.

Chambers. I will accept the correction as to those specific small percentage differences. I suspect that all of us recognize that any of these guesses are merely best guesses at this stage. However, I don't think this change detracts from the general thesis. If you increase the percentage by 10, it

may increase the time we have by 12 years before we reach the situation in which we're in trouble again, so it doesn't affect the main thesis I was trying to convey.

W. J. O'Connell (for San Francisco Bay Area Air Pollution Control District). The Federal Government, as a major purchaser of diesels and as a governing authority for interstate trucks and buses, should: (1) carry out or pay for engineering developments to control odorous emissions that cause localized annoyances almost everywhere in the United States; (2) require Interstate Commerce Commission (ICC) vehicles to install odor control equipment; (3) require ICC vehicles to maintain. smoke-control procedures; (4) procure Government vehicles only with odor control equipment; (5) require Federal vehicles to conform to smokecontrol procedures.

Richard A. Wolff. Mr. Chandler mentioned that it's time, after 10 years of effort on the part of the Automobile Manufacturers Association, to perfect something in the way of a crankcase device or blowby device. And he also mentioned that the devices will be installed-voluntarily, as we all know-on all 1963 cars. About 3 years ago and again about 2 years ago, a very impressive group. came into our Department of Air Pollution Control in New York City and vehemently pointed out that the crankcase device, although very fine in California or parts of California, was not necessary at all in New York City or in other cities aside from Los Angeles County. I should like to know whether or not Mr. Chandler, speaking for his committee, feels now that New York City will benefit in its fight against air pollution through the installation of crankcase devices.

Chandler. The best way I can answer that question is to read the appropriate statement in my paper. "Performance was deemed sufficiently satisfactory, however, so that when the U.S. Department of Health, Education, and Welfare stated that installation of blowby devices on a nationwide basis would be beneficial, industry was ready to announce that the 1963 vehicles would be so equipped." I don't believe that the industry is totally competent to judge the effects within the various communities. That is why we have suggested that each community define its own problems, with the help, of course, of the Public Health Service.

Wolff. I won't prolong this. I think there is a difference between the Automobile Manufacturers

Association going along with the idea because of the feelings of the Public Health Service, and others, and including it in their "voluntary" program because they feel it is a worthwhile endeavor.

Chandler. Your point is well taken. I think one of the reasons that made it easy for us to make this decision is that the reduction was as significant as it was. We're talking in terms of a 40-percent reduction of hydrocarbons at a relatively small expense. I think it's worth the gamble to install these devices in order to achieve these reductions as soon as possible. Obviously, research must be done to determine the need nationwide and, of course, that work is now being done.

Genaro G. Costantino. Mr. Chandler, in view of the established fact that the vapors extracted from the crankcase to be recycled back to the combustion chamber contain harmful ingredients such as metallic fuzz, carbon, varnish, acid, etc., why aren't effective prefilters used on blowby devices to remove the impurities? Is it not reasonable to assume that if these impurities reach the engine, engine wear may be accelerated, causing a drop in engine efficiency and thus resulting in increased blowby? On this assumption, will crankcase blowby devices do more harm than good unless prefilters are used? Also, will lack of proper maintenance of the blowby devices result in poor engine performance, thereby also increasing the crankcase blowby?

Chandler. In answer to your first question, if you will examine the engines being built today which contain blowby devices, I think you will find prefilters. Some of them are not readily visible. They are buried inside the engine with the oil separators. Every effort is made to clean the vapors before putting them back in the engine. Several systems, for example, put some of the vapors into the dirty side of the air cleaner. So I would say that the engines which contain these devices have taken note of the fact that the vapor should be cleaned as much as possible. This, to me, seems to revoke your second question on excessive wear. Obviously, we endeavor to build engines that do not have excessive wear. I think our recent warranties of 24 months, or 24,000 miles, prove that statement, and when a car reaches 100,000 miles, we'd like to sell the customer another one. So that gives us a pretty strong incentive to make sure that our engines do not wear out prematurely. Your third question was: Will lack of proper maintenance result in poor engine performance and thereby increase blowby?

If a ventilation valve is used and it becomes stuck, I think the biggest problem is that you may have backflow through the filler pipe; then you will detect odor and be unhappy and maybe have the valve cleaned. Basically, I don't think there will be any noticeable letdown in engine performance, but this is a tough question. The answer again depends upon engine condition, mileage, and a variety of factors.

Robert I. Sewall. Mr. Maga, don't you think there is a direct relationship between the amount of air pollution and the extent to which a city's population drives to work or takes advantage of public transportation, especially public transportation which does not use internal combustion engine power? Also, don't you think this represents an

other avenue of approach to the problem of air. pollution?

Maga. Certainly. The extent of the motorvehicle-created air pollution problem is related to the number of vehicles and to the amount of fuel burned. Any steps taken to reduce the total number of vehicles used in metropolitan areas would have the effect of also reducing atmospheric concentrations of pollutants from motor vehicles. While we cannot look to mass transportation as the sole answer to the problem, it will be of benefit by decreasing vehicle use in areas with air pollution problems. It would be incorrect, however, to conclude that mass transit systems will do away with the need for the control of motor vehicle crankcase and rear exhaust emissions.

CONCLUDING REMARKS

JOHN D. CAPLAN Chairman

Vehicle Combustion Products Committee Automobile Manufacturers Association Detroit, Mich.

I

First, I'd like to mention briefly a thought of Dr. Chambers' that I think we should consider. In our ignorance, we must be careful, to use a phrase he likes, not to do violence by selective control of ingredients. When we don't understand the process involved in our air pollution problem, we may through ignorance and selective control actually make things worse. This is one of the messages I've gotten from Dr. Chambers' comments. think it's important because, for instance, nontechnical people get frustrated and impatient-as Senator Williams seemed to do yesterday-with this constant demand for research and more research. This is understandable. Yet, as a responsible public official, I'm certain he would agree that such research is vital if we're going to make the correct decisions. And therefore, I think it behooves such officials to depend upon competent and impartial experts such as Dr. Chambers for guidance in these matters. Mr. Marsh also indicates that the public too, who sometimes get impatient with the neverending research, will accept reasonable solutions to the motor vehicle problem if this is explained to them and they are not required to make a selection between scientific opinions from conflicting sources. In other words, the citizen doesn't want to be a party to the old shell game of paying his money and taking his chance that his investment may do some good. He wants some reasonable assurance of success.

With respect to the effect of motor vehicles on health and property, Dr. Nelson certainly was given a most difficult assignment. The fact that he had to resort to a discussion of effects of air pollutants in general is actually a reflection of the fact that we're still not in a position to give definite state

ments to the motoring public that, if we do this to vehicles or we do that to vehicles, this will occur or that will occur. And to quote Dr. Nelson, "We still can't allocate observed effects to sources of specific origin."

Mr. Chandler talked about the future of powerplants and everybody has thoughts along this line. It amuses me to observe that when we're talking about a field other than our own, it is easy to make suggestions as to what should be done. For instance, the gentleman from Providence (Mr. Costantino) today indicated what should be done in designing blowby devices. The point I want to make is that alternative sources of power have been and will be evaluated and were a matter of concern long before the motor vehicle industry became aware of the air pollution aspect. In other words, for the last 50 years this has been one of our constant endeavors. So it isn't untrodden soil and virgin territory when we said that we will have these unique developments in time. My reason for emphasizing this is to point out that although we shouldn't base our immediate hopes on this, it does promise a long-term solution.

When reading Congressman Schenck's remarks, I was confused on one point. For instance, he emphasized that those who design motor vehicles are in the best position to deal with the problem of vehicle emissions, and yet he also stated that the Federal Government should work in the field of establishing a better relationship between design and emissions. Now these two statements could be construed as being mutually contradictory. But perhaps this is just a reflection of environmental effect from the city we're in or, to phrase it another way, anything you can do, we can do better. Finally,

I was impressed with the remarks that Mr. Bright made on the problems of enforcement in administering vehicle control. It occurred to me, in view of the complex problems and the manpower and time involved, that perhaps in a few years the cost of the control devices themselves is not going to be so important. It may be a case of the tail wagging the dog, and the administrative and enforcement costs may be the principal burden that the motorist has to bear. When we consider implementing programs, we should look not only at direct costs of a device but also at the administrative costs and the enforcement costs, because such costs are just as real in dollars as are any of the other costs. I seemed to sense a general agreement among a number of the authors and discussants on this matter of philosophy. In other words, Mr. Marsh, Mr. Maga, Mr. Chandler, and Mr. Bright have been in rapport on what constitutes a sensible and logical approach for a community to follow in establishing motor vehicle control. Mr. Maga was quite modest when he said that his was an approach you could consider. I think he was overly modest. And I think all the groups in California responsible for setting up this program certainly have given considerable thought to what is a reasonable and sensible solution. However, we must remember that although we may agree on the techniques and the operations through which we establish a program or the necessity for a program, the procedure is not worth a thing unless the facts and the data we feed into it are correct. Otherwise, we arrive at the wrong goal and, as an example, I call your attention to Mr. Hass' comments and Dr. Chambers' reply; even in the matter of factual information, evidently we're not all in complete agreement. Similarly, Mr. Marsh's pleas for informing the public lead me to issue a warning; it is important not only that we inform the public but also that we inform the public correctly. In the long run I have confidence that the American public will eventually reach the right conclusion, and you'd better be sure you're giving the public the correct information! Finally, I'd like to summarize the discussions and I think this can be done in one sentence. There seemed to be little questioning of the philosophy, such as whether to control or not to control, or how to determine what is necessary; the main differences of opinion seemed to be based on a lack of agreement on the facts. So, in this respect, things haven't changed too greatly since the 1948 conference.

SUPPLEMENTARY STATEMENT SUBMITTED for the RECORD

THE HAZARDS OF DIESEL AND AUTOMOTIVE EXHAUSTS TO THE EXTREMELY SUSCEPTIBLE PERSON

MARSEILLE SPETZ, M.D. Arcata, Calif.

(A preliminary account of this case was submitted at the conference. This is an extended discussion of the same case.)

Consideration of the health hazard of motor fumes is generally oriented to the average person. There are, however, some people who are unusually susceptible to chemical air pollutants from several sources. A large dose of exhaust fumes in these patients can prove fatal. This is especially true. if the patient has taken care to avoid incitant chemicals, so that an exposure finds the patient in an unusually susceptible state. A small amount of chronic exposure to fumes will keep a person in some degree of adaptation, so that moderate increases in dosage are not reflected in a sharp reactive response. People in a stage of adaptation to small doses of chemical air pollutants may be chronically ill without being aware of the incitants of the illness.

An example of a response in an acutely susceptible patient was furnished me on the way to this meeting. I traveled to this conference with another doctor and his wife. This woman is particularly susceptible to all chemical air pollutants. On our trip here Sunday, 6 hours of exposure to the fumes. of moderate truck travel on the Pennsylvania Turnpike brought on an acute reaction consisting of a state of temporary paralysis of one side, with a Parkinsonian-like tremor, severe migraine headache, and finally; stupor. Fortunately, with administration of alkali by mouth, and oxygen inhalation, she was recovered by the next morning.

Patients can be protected to some extent from motor exhaust fumes by breathing through an activated carbon filter. However, this precaution was not adequate to protect this patient from this particular exposure, even though she breathed through it continually during the period of maximum air pollution.

This reaction to motor exhausts is, in effect, an acute allergic reaction. The predominant cellular abnormality seems to be a cellular acidosis. Prompt administration of alkali by mouth and oxygen in