Comparing shearing shed dust and bioaerosol concentrations over a three-year period

Many variables are associated with the environmental dust and bioaerosol sampling in animal handling facilities. These variables can impact on the concentrations measured and often cannot be controlled. Concentrations of airborne pollens and grasses change between seasons, while ambient air temperatures vary throughout the day. Other variables include the region in which the animal handling facility is located, and its general design. These variables make it difficult to compare airborne concentrations from different facilities. Animal handling facilities are usually enclosed, resulting in the build-up of airborne contaminants to concentrations that may be potentially hazardous to the respiratory health of workers in the buildings. This paper discusses du st (both respirable and inspirable) and bioaerosol concentrations measured in a sheep shearing shed that was sampled over a three-year period. Although the recorded dust concentrations were similar between the three collection periods, the bioaerosol concentrations varied greatly. The possible reasons for the variations (including temperature, ventilation rate and flooring type) are discussed. In addition, the current literature on possible bioaerosol and animal-related dust exposure standards is reviewed.