LETTERS Sager interview Dear Sir: I am writing to congratulate your office, with the absolute approval of the head of this department, on your cover of the December 1973 issue. The refreshing change as far as covers of this day and age are concerned was indeed a strong incentive to see inside the journal. Once again we were pleasantly surprised to read that it was a photograph of Dr. Martha C. Sager, the chairman of the Effluent Standards and Water Quality Information Advisory Committee. We would graciously congratulate Dr. Sager too as there are so many of the mature ladies even in Rhodesia fulfilling key positions with little or no recognition. We do not wish in any way to usurp men's positions but I am sure you will agree that every human being is encouraged by a little appreciation. I t was most satisfying to see that, in spite of Hollywood and the many others, the true value of experience and womanhood is commended and promoted. Our sincere congratulations.
Dear Sir: I read with great interest your editorial "Who's Afraid of Small Particles?" (ES&T, Dec. 1973, p 1085). Your editorial is most timely and I concur with your statements. At Purdue University, I am directing the Industrial Source Sampling Phase of an NSF-funded Research Project in which we are working with a number of industrial collaborators. One of the prime objectives of the project is to characterize the flow of particulates into the atmosphere via stack gas streams. Particle size distribution of these particulates and subsequent analyses for trace metals, particle morphology, etc., have been and are being carried out. At the present time we have some very interesting results from stack gas streams from power plants, zinc smelters, and the Northwest Indiana steel mill operation. Robert 6 . Jacko Purdue University West Lafayette, Ind. 47907
1973, p 1085) indicates in two places, that there is no commercial equipment available to measure small particles-"less thqn 3 micron s. " Bausch & Lomb has manufactured and sold in the commercial and military markets for at least eight years, an aerosol counter which covers the size range of 0.3 micrometer to greater than 10 micrometers. There' are at least four other companies which manufacture and sell similar type equipment. I refer to your own publication, ( E S & T , Oct. 1967, p 801-4) showing test results of existing equipment or prototypes which resulted in commercially available equipment. Editorials can be and usually are useful means for stirring up the status quo. However, their impact is reduced or nullified if the editor shows his ignorance of the subject by including statements which are not true. Your editorial did not fall on deaf ears in this case, but its impact on my current activities is probably nil.
Mrs. Rosaleen Kerr Government Analyst's Laboratory Salisbury, Rhodesia
Small particles instrumentation Dear Sir: The editorial ( E S & T . Dec.
Douglas D. Doonan Bausch & Lornb Rochester, N.Y. 14625
Small particles
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