At present, there is no systematic online or offline training institution to provide teaching courses except formaldehyde. If you want to enter in addition to formaldehyde, you must first know what the so-called in addition to formaldehyde does. Accurately speaking, in addition to formaldehyde not only removes formaldehyde, but also refers to indoor air treatment. If you want to engage in indoor air treatment projects, you must first understand the main sources of indoor pollution and relevant national standards.