Occupational exposure limit for maleic anhydride in workshop air

May I ask what kind of workshop you are in? What is being produced?

Maleic anhydride is another name for succinic anhydride; it is a flammable substance that appears as colorless needle-shaped crystals, and it is soluble in water, acetone, benzene, chloroform, and most other organic solvents. Its melting point is 52.8°C, boiling point is 202°C, and flash point is 101.6°C. It poses a risk of combustion when exposed to high temperatures, open flames, or oxidizing agents, and it is corrosive. The dust and vapor of this product are irritating. Inhalation can cause pharyngitis, laryngitis, and bronchitis. It may be accompanied by abdominal pain. Direct contact with the eyes and skin has a significant irritating effect and can cause burns. Prolonged exposure to this product can cause chronic conjunctivitis, nasal mucosa ulcers, and inflammation ； It is allergenic and can cause rashes and asthma. The oral LD50 in rats is 400 mg/kg. The oral LD50 in mice is 60–465 mg/kg. In the United States, the maximum allowable concentration in the air is 0.25 ppm. Former Soviet Union: Maximum allowable concentration of harmful substances in workshop air – 1 mg/m3. Former Soviet Union (1975): Maximum allowable concentration of harmful substances in atmospheric air in residential areas – 0.2 mg/m3 (peak value), 0.05 mg/m3 (average daily value). Former Soviet Union (1975): Maximum allowable concentration of organic substances in water – 1.0 mg/L. Former Soviet Union (1975): Maximum allowable concentration of organic substances in wastewater – 10 mg/L :lol :victory:

According to \"Occupational Exposure Limits for Hazardous Factors in the Workplace _ Chemical Hazardous Factors\" (GBZ2.1-2007), the PC-TWA is 1 mg/m3, the PC-STEL is 2 mg/m3, and no value is specified for MAC. Data from other sources cannot be used in our country as they are not yet recognized. The standards of the former Soviet Union are long outdated.