THE TEMPORAL VARIATION OF AIRBORNE FINE DUST CONCENTRATION IN PIG FATTENING HOUSES - HYGIENIC AND MEDICAL ASPECTS

The temporal variation of airborne dust concentration (less-than-or-equal-to 10-mu-m) was examined with an instrument operating on the nephelometer principle combined with a specifically adapted data processor in two pig fattening houses at night, at day and during feeding. Activities and factors affecting the dust level were noted. The measurement system allows the uptake and storage of values in the stable. For further processing, the data can be transmitted to a personal computer. In our experience the instrument is very suitable for the registration of airborne dust concentration in animal confinement buildings. Peak concentrations ranging up to 100 mg/m3 in intervals of 10 seconds could be measured. The data of a longer trial were averaged over 1.5 minutes. Animal activity has a great influence on the dust concentration. The highest mean concentration of dust with maximally 2.5 mg/m3 were determined at feeding time and when pigs were disturbed. The concentration of airborne dust particles was obviously lower at night than at day. A defect of the ventilation system, referable to the immission of feed dust, was disclosed by the continuous registration of air dust concentration, in one of the pig fattening houses. During the feeding periods, for a short time of less than 20 seconds, the dust concentration rises to 100 mg/m3 resp. 27 mg/m3 by dry resp. wet feeding. About 30 minutes after feeding the dust concentration was again in the average of 0.67 mg/m3. In conclusion the results were considered under hygienic and medical aspects.