In Holland again there was an explosion in a modern freestall barn with a certified low ammonia exhaust label. Also this third barn had a so called semi closed floor with a manure pit underneath. Ammonia and methane from the manure can hardly emit which makes this type of barn environmental friendly according to official guidelines. It is unclear yet what caused the explosion. It happened during mixing the manure. The concrete floor came up one metre and fell back into the manure pit and broke. Twenty cows fell also in the manure pit. The fire brigade with help of a crane and making a stairs from straw bales took the cows out of the pit.