The protocol presented is dedicated to evaluation of additives in laboratory using a heated water-bath where the manure samples put in glass containers are placed. Air samples are extracted from those container for olfactometry evaluation and analysis for ammonia. The costs of common slurry additives is presented as ranging from 10 to 60 DM (6 to 35 US$) per livestock unit (500 kg live weight) per year. Ammonia reduction of 46%, 53% and 64% was obtained with rapeseed oil mix to the manure to form a top layer for addition of 20, 40 and 60 l of oil /m3 of manure.

No links are made between the results of those tests done under controlled conditions and what can happen in real scale situation.