Back in the seventies there were no international guidelines for calculations on indoor climate in animal houses. Each country had its own calculation methods, why a group of leaders at research institutes and universities, in the field of Agricultural Building, decided in 1976 at a CIGR mee-ting, to create a working group on Climatization of Animal Houses. The working group held its first meeting in 1977 in Switzerland, and consisted of 11 scientists from 11 European countries and some corresponding overseas members. CIGR was not yet real internationally in scope at that time. S?ren Pedersen was appointed as the Danish member and was for him the start of nearly four decades of international work on Climatization of animal houses and it has brought S?ren Pedersen around to several international symposiums, conferences and congresses. His first Congress was in Budapest in 1984, where Hungarian, Russian German, French and English were official languages, with simultaneously interpretation.
It was expected that the work in the above mentioned working group, should be finished in two year time, but due to several obstacles it took the time until 1984 to finish the first report. E.g. the first draft in 1977 was elaborated in German language, illustrating that it was not clear at that time that the international conference languages would be English. Furthermore it was a hard work to come to a common agreement on animal heat and moisture production, based on 11 different national standards.
The employment of the calculation rules in the 1984 report shoved good agreement with praxis on a 24 hour basis, but it was evident, that in some cases there could be big deviations during the 24 hour cycle, due to e.g. animal activity. Unfortunately no equipment was available for measuring animal activity, why S?ren Pedersen developed an equipment based on Passive Infrared Detectors. The measurement shoved that most of the diurnal variation in animal heat and moisture production could be explained by diurnal variations in animal activity. This measuring principle was thereafter taken into use at several European universities. The method was published in 1995 and followed by a number of articles. Besides the impact of animal activity, also the digestion of feed contributes to the total animal heat production. Therefore Pedersen et al., included the digestion into the model, published as: The Influence of diurnal variation in animal activity and digestion on animal heat production, Agric Eng Int: CIGR Journal, Special Issue, May 2015.