A comprehensive experimental study of aerial pollutants in and emissions from livestock buildings. Part 1. Methods

Airborne pollutants in, and emissions from livestock buildings affect animal and human health and welfare and contribute to environmental air pollution. Field surveys have shown the influence of livestock species and management strategies on pollutant emissions. However, to verify these field survey measurements and to ensure representative results from short-term studies, a comprehensive experimental study in both a force-ventilated fattening piggery and a naturally-ventilated broiler house was also carried out, to achieve measurements with a high resolution in position and time. For the force-ventilated piggery, ventilation rate was measured directly using fan-wheel anemometers and by the CO2 balance method. Inhalable dust concentration was measured with a gravimetric procedure, while a micro-balance using a mass-sensitive oscillator allowed additional on-line measurements of dust concentration, e.g. for comparison with measured levels of animal activity. Concentrations of the gaseous components CO2 and NH3 were detected mainly using a photo-acoustic multi-gas monitor. For NH3 only, absorption tube and wet chemical analysis were also used. This suite of methods enabled comprehensive studies of the behaviour of airborne pollutants in and emissions from livestock buildings. The results are reported in Part 2 of this paper. (C) 1998 Silsoe Research Institute.