Burns due to acids and alkalies are most common with sulfuric acid, hydrochloric acid, and nitric acid. In addition, there are acetic acid (glacial acetic acid), hydrofluoric acid, perchloric acid, and chromic acid, all of which are corrosive poisons. In addition to skin burns, inhalation of the volatile gases and mist points of these acids (such as sulfuric acid mist and chromic acid mist) into the respiratory tract can also cause severe irritation of the upper respiratory tract. In severe cases, chemical bronchitis, pneumonia, and pulmonary edema may occur. Alkali burns are more common in ammonia, sodium hydroxide, potassium hydroxide, and lime burns. The most common is ammonia burns, which are often accompanied by upper respiratory tract burns due to its high volatility, and severe cases also have pulmonary edema. Eyes are prone to erosion if a small amount of diluted ammonia is splashed into them, and the healing process is slow.