Two long-term datasets of high-frequency ammonia emission
measurements, from a conventional and a low emission
fattening pig housing facility were used to evaluate different
reduced sampling strategies. In contrast to previous work on
reduced sampling strategies, this study is based on emission
data only, disregarding any other parameters that affect the
emission.
Short term sampling strategies such a single grab sample, a
24-h or 48-h high frequency monitoring period or a 7-d high
frequency monitoring period provide less accurate and less
precise emission estimates than a low frequency strategy
consisting of weekly grab samples carried out throughout the
production cycle, although the practical restrictions that
occur because weekly grab samples can only be taken during
the working day can cause a bias leading to an overestimation
of emissions.
Repeating the short-term high-frequency sampling events
throughout the production cycle could alleviate their lack of
precision, while the length of the weekly grab sampling
strategy could be reduced without sacrificing too much pre-
cision. As the cost and effort of monitoring increase with the
number of repeated sampling events, or the length of a weekly
sampling strategy, the resources required should be balanced
against the required precision. The present contribution