Accidental spills of liquid ammonia can result in the formation of deadly, fog-like ovoids of ammonia droplets that persist for an appreciably time before dissipating. The addition of a coalescing additive such as urea to liquid ammonia reduces the size and persistence of the cloud that can form if the treated ammonia is accidentally released to the atmosphere. The potential for death and injury resulting from an accidental release of ammonia is thus substantially reduced.