Car urea must be stored between -5 degrees -25 degrees available. And the storage temperature is not the same in different shelf life, when the temperature exceeds 35 degrees, the vehicle must be tested prior to use of urea. About Car urea solution, the domestic industry experts had certain environmental impact tests. A stability test; storage-stable, thermally stable at 50 ℃ conditions, only a small amount of free ammonia produced, but under conditions of 100 hours 70 ℃, found free ammonia content than the standard maximum 0.2%, and at 350 hours Under a long time to reach 1.4% of free ammonia. So urea solution storage temperature should be at 50 ℃, a single-temperature impact indicators is likely to cause hydrolysis. B field experiments; processing experiments mainly in cans, cleaning, overflow, etc., motivation performing experiments (-4 ℃ to -8 ℃), the experimental operation in summer (above 32 ℃) C compatibility with other substances; concrete, metal containers plastic containers, closures. Vehicle concrete urea solution and poor compatibility. Plastic products without any compatibility with polysulfide seal compatibility test concluded no compatibility.