Class A four-piece set refers to products used by infants, with formaldehyde content not exceeding 20mg/kg and pH value between 4.0 and 7.5. No odor is required, and carcinogenic aromatic amines cannot be used. There are also strict regulations on dyeing fastness. These regulations are designed to ensure the health and safety of infants and young children. A-class four-piece suit is made of pure natural fiber and organic fiber, which has good air permeability and hygroscopicity, can keep bedding dry and comfortable, has no irritation to skin and is not easy to cause allergic reaction.
Class B four-piece suit is a product that comes into direct contact with the skin and is suitable for adults and children. Its formaldehyde content should not exceed 75 mg/kg, and its pH value and odor are also regulated accordingly, which is slightly lower than the Class A standard. Class B four-piece suit is made of chemical fiber, such as polyester, acrylic and nylon. , in line with national standards, long-term exposure may have a certain impact on the human body. Its permeability and hygroscopicity are poor, and it is easy to generate static electricity, which is irritating to the skin.