Because lying in bed smoking, a little careless, the cigarette butt will be drawn on the bedding. And Article 14 of "Twenty Articles of Common Sense of Fire Safety" stipulates: Do not smoke in bed or on the sofa, and do not throw cigarette butts.

When a fire occurs, especially after the body is tired or drunk, people often fall asleep before they finish smoking, resulting in the cigarette butts burning with combustible materials such as bedding and mosquito nets.

The temperature of a lit cigarette can reach 700 °C, and the continuous burning time of a cigarette is about 15 minutes, and the spontaneous ignition point of common combustibles is very low, such as paper, cotton, linen and its fabrics, etc. Most of the ignition points are 200 ° C to 300 ° C, and the temperature of cigarettes after ignition is 2 to 3 times higher than the ignition temperature of these solid combustibles.

Therefore, unextinguished cigarette butts are enough to cause solid combustibles and flammable liquids and gases to catch fire.