Dust concentrations were reduced by 35-60% in pig buildings, while human dust exposure was lowered by 50-70% by adding 4% animal fat to the feed. However, there is still a large quantity of airborne dust in these buildings and workers should reduce their exposure risk to the high concentrations by wearing a dust mask. Variations exist in dust concentrations for total dust in pig buildings. The respirable dust fraction does not appear to be location-dependent and therefore may be a better indicator for evaluating dust reduction methods. Further studies are needed to find the nature of these variations in total dust concentration, so that a representative measurement can be determined for a pig building. Total dust levels found by a personal sampler were from three to seven times larger than total dust concentrations measured by a stationary sampler. Relationships between values from personal and stationary dust samplers need to be explored for livestock environments, and improved dust measurement criteria established for evaluating dust suppression practices.
Bibliographical noteFunding Information:
This study was funded by the Danish Agricultural and Veterinary Research Council. The authors would also like to thank H. T. Søgaard for valuable discussions on the statistical analysis of the results.