Mercury thermometer in the measurement of body temperature, due to improper use, may lead to give broken, the metal of the mercury may volatilize dispersed in the air, usually the maximum permissible concentration of metal mercury in the air is 0.01 p.p.m. / m³. In general, people in the mercury so the concentration of 1.2-8㎎/m³ environment will soon cause poisoning. A mercury thermometer contains 1g of mercury broken up and dropped on the floor of a room of 15m². If the mercury is completely volatilized, the concentration of mercury in the indoor air can reach 22㎎/m³, a figure that far exceeds the permissible standard and can seriously jeopardize human health. Therefore, once the mercury thermometer broken, immediately after the mercury to deal with clean sealing, and then thrown into the garbage, timely window ventilation, you can also use some chemical substances such as potassium permanganate on the ground mixed with mercury, dissolve the mercury. Never pour mercury into the sewer to avoid contamination of groundwater sources. Therefore, after the mercury thermometer broken, mercury if handled properly, generally will not cause baby poisoning.