This question examines the classification of occupational health and safety accidents. According to the Classification Standard for Casualty Accidents of Enterprise Employees (GB 6441-KLOC-0/986), the accident categories are divided into 20 categories, namely, object strike, vehicle injury, mechanical injury, lifting injury, electric shock, drowning, burning, fire, falling from a height, collapse, roof caving, water seepage, blasting, gas explosion and gunpowder.