Hazardous gas poisoning patients will have sudden onset of dizziness, headache, accompanied by confusion, blurred consciousness, vision rotation, blurred vision, as well as a transient darkness in front of the eyes, some patients will also have tinnitus, deafness, etc., and in severe cases, there will be coma, convulsions, loss of consciousness, diaphoretic incontinence, and in severe cases, there will also be a sudden death, also known as flash cells. Harmful gas poisoning also causes circulatory dysfunction, and patients may experience chest tightness, shortness of breath, palpitations, and discomfort in the precordial area accompanied by chest pain. Patients may also experience respiratory symptoms, with coughing, coughing up sputum, wheezing, shortness of breath, and in severe cases, severe dyspnea.