Document wgqnKRyggEm09xz3o8KVJ8jp3

DUST SURVEY OF THE DAYTON POWER AM) LIGHT COMPAMY GARASE: . February 26, l^ip- ;^ The purpose of this survey is to study the methods of instrumentation to he used in a dust survey of atmospheres polluted by exhaust gases from automobile engines. The main question involved in instrumentation is the question of whether or not some lead exhausted from engines might be in the form of organic vapors which would not be collected by the electrostatic precipitator. In order to check this question, atmospheres in the garage, which were known to contain high con centrations of exhaust gases, were sampled by an electrostatic precipitator in series with an activated charcoal absorber. Simultaneously with this series of samples, another precipitator sample was taken without the charcoal absorber. In several instances simultaneous impinger samples were taken also. i - - In processing the samples, those which were taken in the precipitator in series with the charcoal absorber were washed from the tubes with dilute nitric acid (5/^)* The other precipitator samples were intended to be washed with absolute alcohol, to be used for the purpose of making dust counts for comparison with dust counts made on the impinger samples. The latter purpose, however, was not fulfilled because the work was delayed so long after collect ion of the samples that it was thought the impinger samples might have been dissolved to such an extent as to make the count worthless. -2' The actual procedure involved was the washing of one set of precipitator tubes with nitric acid as planned, the analysis of these washings and of the charcoal from the absorber for lead, the washing of the other set of precipitator samples in alcohol, and the making of dust counts on these washings. The samples were taken in locations as follows. Samples #iplCl, 2, 3, and Ip were taken at the edge of the driveway through the first floor midway between front and rear doors. The room in which these samples were taken was the repair shop; and at the time they were taken (7:30 to 8:00 a.m.) traffic was limited to one or two trucks passing through on the way in or out. Samples #i}LCl and #1(1102 were precipitator samples. #ij.Q.C3 was a charcoal sample taken in series with sample #klCl. #kG.Cl|_ was an impinger sample. All four samples were taken simultaneously. Samples #L}fXC5* and 7 were taken on the second floor of the garage in the passage way between the two rooms of the storage garage. At the time these samples were taken (8:30-9*00 a.m.) most of the cars stored in the garage had been removed, but there was. an occasional car moved during the sampling process and these cars passed within six feet of the sampling instruments. #I|0LC5 and #ljilc6 were precipitator samples and #1(3.07 was a charcoal sample taken in series with #k&C5. Samples #l|LC8 and 9 were two precipitator samples taken at the same locations as #1(3.05, and 7 immediately following (9:00-9:30 am.). KS 0015305' -3- Sample.s #lj.Q.C10, 11,, and 12 were taken near the window in. front of the lubrication rack on the west side of the first floor. At this time (.9^5-10:15 a.m.) the only engines running in the shop were those under repair which were merely being run at short intervals for test. #kQ.G10 and 11 were precipitator samples and #ljLC12 was an impinger sample taken simultaneously. Samples -ylfLClp, 1k, and 15 were taken in the stock room on the first floor which is east of the repair shop mentioned above. The sampling point was midway between front and rear doors and at the end of the driveway. Traffic during the time of sampling (10:20-10:50 a.m.) consisted of three large trucks which drove through the room in succession, each stopping for a few minutes to be loaded. Jfhfi.ClJ and llj. were precipitator samples and C15 was an impinger sample, all taken simultaneously. Samples #ljfl.Cl6 and 17 were simultaneous precipitator samples taken on the second floor at the same location as #1405, 6, and 7 ( 5?50-kil0 p.m.). Sample -#k&0l6 was taken in a specially coated glass tube, which was an experimental tube obtained from the Mine Safety Appliances Company. The other sample v/as taken in an aluminum tube, the purpose of these two samples being to check the glass tube against the aluminum tube for quantitative collection of lead dust. Samples #klCl8, 19, 20, and 21 were taken at the same location as #I|d-C5, 6, and 7, at a time (k:20-k:5 P*m*) when the cars to be stored in the storage garage were being returned for the night. There was a steady flow of traffic within six feet of Hi 00159 0'6 the Instrtiinents. #k&Cl8.and 19 were precipitator samples. #1$.C20 was a charcoal sample in series with #^018. #ljLC21 was an impinger sample. #I|.1C22, 23, and 2k were taken at the same location again as #klC5, 6, and 7, and.at this time (k:50-520 p.m.) traffic was still flov/ing passed the instruments steadily hut with slightly diminished rate. #i|lC22 and 23 were precipitator samples and #klC2ij. was a charcoal sample taken in series with #Ij_lC22. The results of lead analysis for precipitator and char coal samples are summarized in Table I. The results of dust counts made on the other precipitator samples are given in Table II. William R. Gall KT 0015907 TABLE I Sample Ttumber Total Pb Found Total Vol. of air cu. ft. kOC-l 0.325 0.375 . kOC-5 1 0.275 1k)C~" 7* p|"-- 0., 0 30-- -- r'L] itOC-9 1 0.088 ------1---- -------1------ M------- -------- koc-n 0.033 kOC-lk 0.073 kO;C-l6 0.03k kOC-l? 0.035 k0C-19 0.0825 kQC-20 0.220 kOC-22 0.0675 kO;C-2k 0.2k0 92.70 12.15 108.15 ik.ko 92.70 92.70 92.70 61.80 61.80 92.70 8.77 92.70 -- ,Ou.-- f t. Pb Con centration Mg./10 Cu. M. Remarks O.2625 0.03kk 0,3063 0 40k08 i 0.2625 0.2625 0.2625 0.1750 0.1750 0.2625 G.02k8 , 0.2625 0.0271 T ! 1 f 1.2580 jq Charcoal'Sample 0.8978 0*7353 J; Charcoal Sample 0*5352.......ki 0.1257 0.2781 0.l9k3 0.2000 Glass tube Check on glass tut o.3ik3 v 8.8710 Charcoal Sample. 0.2571 8.8561 1 Charcoal Sample TABLE II Sample ilumber kOC-2 koc-k koc-6 k0c-8 koc-10 koc-12 koc-13 Dust Count Millions Particles per 10 Cu. M. 35k7 1039 133 183 61 LO ! .-! 001' koc-18 k0C-21 K*r k78 0015908:; Dust Count Millions Particles per Cu. Foot Remarks IQ-Otoy 2.9k25 0.3767 0.5183 0.1728 1.3537 A ol,0 : Impinger Sample Impinger Sample Impinger Sample Sheet Results invalid; see Analysis/ ^ Impinger Sample