Document mRqOjgKrjowgemmbNoVbMR6O

fping those cstosis Re link on the np devoted J & Parkes en formed customers nd service rxists and, y premises as, by the otvn dust surtmenL to be enmenancc. ietenuine ' of dust ring two will be of bulk to th"se sfo. 4 remind mmend ve what is Ree level. 1 over a pes or health nrfacehand- ountry h. and ervice e with slosis 4a. Om*>. Iln- Vol. n. pc. J'-X. tatunon fwn 1110. Flint** i* Grral DtUai* REMOVING DUSTS FROM BRAKE ASSEMBLIES DURING VEHICLE SERVICING- ALTERNATIVE CLEANING METHODS* G. L Lee British Leyland, Longbridpc, Birmingham PRELIMINARY CONSIDERATIONS Whatever the criticisms may be from an occupational health point of view, few would deny that the operation of removing brake dusts with an air line is efficient in that the total time to perform the task is extremely short. The time required to perform an operation is of vital importance in industry' and any process changes will always be judged relative to the time scale. In addition, the effort required front an operative in using the method should be minimal and it is easy* to sec that the chances of de veloping a technique of cleaning which will reduce dust emissions but at the same time require no more time and effort are extremely slim. Quite dearly, we must concede from the very' beginning that some increase in time and effort involved is inevitable. When viewed under normal lighting conditions, the result of applying a com pressed-air line to remove brake dusts is very dramatic. Unfortunately, mere dramati sation alone is no: adequate to describe the emission of dust from a process; more objective methods are needed. The conventionar method of evaluating an environ mental condition is the measurement of the appropriate parameter (in this case-- .fibre counts), referring the results to hygiene standards, in experimental work to evaluate dust control methods, simpler, "relative" techniques of measurement have considerable advantages and part of this work is concerned with applying a fairly simple method to define certain environmental conditions whieh prevail when brake dusts are removed by blowing out with a compressed air line and comparing these with the conditions obtained when a dust control technique is applied. Because the method is a relative one, care to prevent errors from extraneous sources of variation is important. These sources of error are discussed latei. METHODS USED TO EXAMINE ENVIRONMENTAL CONDITIONS When dusts are released in. relatively small quantities it is often impossible to sec the clouds under normal lighting conditions. They can be made visible using the Tyndall Bum cfTect and this has been employed extensively during the experimental work. *This paper was originally presented at a Conference on Exposure to Asbestos during Brake and Clutch Maintenance, held at Brentwood. Essex, March, 1969. 3}