Document 6bo7nxjEQmER8w0BGRvYqz1BR

FILE NAME: Allied Signal Bendix (ASB) DATE: 1971-1973 DOC#: ASB039 DOCUMENT DESCRIPTION: Bendix Report - Brake Emissions: Emission Measurements from Brake and Clutch Linings from Selected Mobile Sources Report 68-04-0020 BRAKE EMISSIONS: EMISSION MEASUREMENTS FROM BRAKE AND CLUTCH LININGS FROM SELECTED MOBILE SOURCES M. G. Jacko R. T. DuCharme ' ; j Bendix'Research Laboratories Bendix Center Southfield, Mich. 48076 March 1973 Final Report for Period May 1971 - March 1973 Prepared for ENVIRONMENTAL PROTECTION AGENCY Office of Air and Water Programs Ann Arbor, Mich. 48105 Figure 8-11 - Asbestos Fiber in Brake Emission These values are given in Figure 8-13. Then it is necessary to multi.**' the number of fibers given in each box in Figure 8-12 by the volume p, for the corresponding box as shown in Figure 8-13, The typical microscopy count shown in Figure is used to calculate asbestos content in the following manner. The f!k* of each group are totaled as shown in Table 8-5. The total number of fibers per group (n) is then multiplied by the average volume per pj' *t (V) to obtain the product (n x V). All products are then totalled t ' arrive at the total volume of asbestos detected. Since only a fraction of the total area is tually scanned, the volume observed must be normalized to the entire *1 containing wear debris: Total Fiber Volume (by EH or OM) Total Area of Filter = Volume obtained (cc) x (No. of Fields Counted) x (Area of a FioH T- 990 mm = E (n x V) x EF x (Area of Field) 8 -2 0 Table 10-13 - Asbestos Content of Automotive Friction Materials Vehicle and Brake Type Passenger Cars Drum Linings Disc Pads Truck Segments Clutch Facings "Average composition" for use in the calculations in this report. Average Percent Asbestos Content by Weight* 68 + 5 60 + 5 55 + 5 50 + 5 60 `Sources Estimates made for this study. C*? of> 0> CN PERCENT OF DECELERATIONS EXCEEDING g ? a. Figure 10-1 - Frequency Distribution of Braking Decelerations