Different medical history and different etiology. Formaldehyde poisoning and colds are obviously different: first of all, in the symptoms if the patient has formaldehyde poisoning, there will be typical mucosal irritation symptoms, such as inhalation of formaldehyde after the eye conjunctiva and respiratory system within the conjunctiva, such as the nasal mucosa, the mucosa of the oral cavity have obvious burning sensation, burning sensation, the feeling of maladjustment, for such symptoms of patients with colds are not. Secondly, formaldehyde poisoning patients will also have obvious digestive symptoms, such as nausea, vomiting, reluctance to eat or abdominal pain, diarrhea, etc., for patients with colds, such symptoms also do not exist. Then formaldehyde poisoning patients do not have a fever, body temperature is normal, while patients with colds will be accompanied by varying degrees of fever. Finally formaldehyde poisoning will have typical neurological symptoms, such as dizziness, headache and other obvious symptoms.