Sulfur hexafluoride (SF6) is a good gas insulator and is widely used in gas insulation of electronic and electrical equipment. Its typical application is used as gas insulation in the high voltage switch cabinet of power transmission and transformation station, power plant, etc. To protect sulfur hexafluoride, we must first understand the physical and chemical properties of sulfur hexafluoride. Pure sulfur hexafluoride, low toxicity, stable properties. But after inhaling a mixture of 80 percent sulfur hexafluoride plus 20 percent oxygen for a few minutes, people experience numbness in their limbs and mild irritation. Sulfur hexafluoride gas is filled into the high-pressure switch cabinet with a certain pressure, so the probability of gas leakage is high, and the oxygen content in the air is sufficient, which makes the conditions for sulfur hexafluoride to combine with oxygen to produce toxicity after leakage sufficient. This is one of those situations where you need protection.

When the sulfur hexafluoride gas is exposed to high heat and temperatures (such as electric arcs), it produces by-products - sulfur oxide and hydrogen fluoride gases, which coexist with the undecomposed sulfur hexafluoride gas. There are three kinds of poison gas.

Sulfur oxide is a kind of sulfuric anhydride, easy to be absorbed by the mucous membrane surface of the human body to produce sulfuric acid and sulfurous acid, the eye and respiratory tract mucous membrane has a strong stimulation. The symptoms include tears, cough, sore throat, eye conjunctiva and tingling of respiratory tract. Encounter human sweat, will make people's skin red and swollen. Hydrogen fluoride is soluble in water. Hydrofluoric acid, which is also readily absorbed by the body's wet mucous membranes, is just as harmful to the human body as sulphur oxide -- the eye and respiratory tract, but more harmful. Hydrofluoric acid is often used to etch glass, so it is highly corrosive. In case of human sweat, hydrofluoric acid is formed on the surface of human skin. It can penetrate the surface of the skin and penetrate into the deep layer, forming ulcers and necrosis, and should not be cured. If skeletal damage causes skeletal fluorosis, there will be no recovery. Hydrogen fluoride is more toxic than sulfur oxide and sulfur hexafluoride.