1. Coal dust, like combustible dust such as metal dust (such as aluminum powder and magnesium powder), synthetic material dust (such as plastic powder and dye powder) and forest product dust (such as paper powder and wood powder), belongs to explosive dangerous goods. When the concentration of combustible dust mixed with air reaches a certain value, in case of Mars, arc or proper temperature, the oxidation reaction is completed in an instant, and the generated heat and flame are quickly transferred to the adjacent dust, which in turn causes the surrounding dust to burn and release heat.

2. Systemic action: Temporary inhalation of high-concentration dust can cause systemic diseases (pneumoconiosis), accompanied by diffuse and progressive pulmonary fibrosis, such as inhalation of toxic dust such as lead, copper, zinc and manganese, which can be dissolved in the bronchial wall and absorbed, and carried to all parts of the body by blood, causing systemic poisoning. Lead poisoning is chronic, but if the poisoned person has a fever, or takes some medicine and drinks too much wine, it will also cause an acute attack of poisoning.

3. Excessive inhalation of copper dust may lead to hemolytic anemia; Zinc oxide dust is produced when zinc is burned, and metal smog fever similar to malaria occurs after inhalation; Temporary inhalation of manganese and its oxide dust or smoke has adverse effects on the central nervous system, respiratory system and digestive system.

4, local effect: contact or inhalation of dust, first of all, the skin, cornea, mucosa and other local soothing effect, and a series of lesions. If dust acts on the respiratory tract, it can cause hyperfunction of nasal mucosa and telangiectasia in the early stage, and hypertrophic rhinitis will be formed over time.

5. Finally, due to the insufficient supply of mucosal nutrition, atrophic rhinitis is formed. It can also form pharyngitis, laryngitis, trachea and bronchitis. When it acts on the skin, it can form acne, folliculitis and pyoderma. If lead dust penetrates into the skin, some little red dot will appear, which is called "lead rash".