Comprehensive measurements of aerial pollutants
were carried out in a mechanically-ventilated fattening
piggery and in a naturally-ventilated (Louisiana-type)
broiler house. In the piggery, ventilation rate was directly
measured using fan-wheel anemometers and indirectly
estimated by a CO2 balance method. Over 24 h, the
indirect CO2 method underestimated the direct method
by+6)5%. Concentrations of inhalable dust and of the
gases NH3 and CO2 were monitored quasi-continuously
in both buildings. In the piggery gravimetric and wet
chemical measurements were used to investigate the spatial
variation of dust and ammonia concentration, respectively;
only towards the walls were signiAzcant variations
found. Seasonal inAYuences were detected for inhalable
dust concentration in the broiler house and for ammonia
concentration in the piggery. Altogether, the comprehensive
study showed that the results of a related Azeld
survey, which used an array of measuring positions in the
central cross-sectional plane of each livestock building,
were comparable and suA