This
protocol is also currently used in Flanders to determine NH3
emission factors. This extensive, more expensive and time
consuming protocol was followed-up in The Netherlands
using an alternative sampling protocol (a multiple-location
approach), based on measurements at several (i.e. four)
farms provided with the same housing system. This new
protocol prescribes six sampling periods of 24 h for each farm
location, distributed over the year and randomly taken over a
period of two consecutive month period. For animal categories
with growth production cycles (e.g. fattening pigs)
measurements had to be equally divided over the production
cycle (e.g. fattening period)