The nitrogen flow is well explained in this publication. The following opportunities to control ammonia emissions are presented: -limit release from manure by keeping manure solids covered, limiting air velocity over manure liquids and by decreasing the stored manure temperature; -limit the potential for manure accumulation on the room surfaces; -ammonia ventilation control in the room is realized by proper ventilation (control the interior conditions but doesn’t limit the emissions to the atmosphere); -scrubbing can lower or control the emissions to the atmosphere from the air coming out of the livestock building.