VACUUM VERSUS BRUSH CLEANING IN FARM FEED MILLS

The design and layout of farm feed mills does not acknowledge the need for routine cleaning. Cleaning with brushes caused exposure to inspir able dust concentrations of between 22 and 138 mg/m3. Four out of six exposures were in excess of legally defined limits. Cleaning with vacu um equipment caused exposure to inspirable dust concentrations of betw een 0.3 and 32 mg/m3. Vacuum equipment was more effective at removing dust, created a better working environment and was more able to clean awkward areas than cleaning with brushes. Problems with vacuum equipme nt included the weight and blocking of hoses, inappropriate nozzle des igns, and disposal of collected dust. Settled dust concentrations in t he mill areas were highly variable and were not significantly reduced by cleaning the mill area. Vacuum equipment is available on approximat ely 20% of farms with registered feed mills, but are used infrequently . The potential for increasing vacuum use is very high. There are almo st 25 000 fixed and mobile milling and mixing plants in the UK. The ne ed to improve hygiene in the mill area should be promoted within the a gricultural industry.