Document 5D3rLmLZ8q6aVBNE1LX7Jxz3e

IK D. E. Hickisii and K. L. Knight Taule2. Personal samples during car DRAKE SERVICE Sample Concentration (fibres/cm1) 1 2 3 4 5 6 Time-weighted average 0 63 M2 021 0-96 0-38 0-79 0-63 EXPOSURE DURING TRUCK SERVICING Maintenance of truck brakes involves a somewhat different type of operator exposure as the servicing is more complex, and therefore the number of vehicles dealt with is less. The larger size of wheels and drums, on the other hand, makes it difficult for the operator to avoid the dust cloud produced, and personal exposure could be higher than that during car maintenance. Further sampling was therefore carried out in a large fleet workshop with equipment similar to that used for the passenger car tests. Static samples, each of approximately 3 hr duration, were collected during the morning and afternoon periods at three positions; at the bay adjacent to the one at which brake cleaning was carried out, at the next bay, and in the centre of the garage. Brakes were blown out during the morning, but not during the afternoon. The resufts arc given in Table 3. Table 3. General atmosphere samples during truck drake service Location of sample Concentration (fibres/cm1) Adjacent bay 2 Bays away Centre of garage Morning Afternoon Morning Afternoon Morning Afternoon 0-28 0 07 017 007 0-49 Oil Personal samples were obtained from two men--the man engaged on brake cleaning, and the man engaged on clutch repair work at the adjacent bay. The first period of 1-5-2 hr included the period of brake cleaning, and the second period of approximately 5 hr represented the remainder of the shift. The results are shown