A large cloud of carbon dioxide hangs over Lake Nios and the surrounding plain near the border of Cameroon and Nigeria on 21 August 1986. Recent killed 1,746 residents of nearby villages and more than 3,000 animals. To the lake 400 years old, for decades been circulating myths and legends, which were confirmed during this priodni kaastrofe. Farmers who live near Lake Nios in the middle of the night, they heard a roar and then the lake drained hundreds of thousands of carbon dioxide (CO2) and formed a cloud, but estimates range from 300,000 to as much as 1.6 million tons. It was the first time that a natural phenomenon caused the suffocation of so many people and animals. The cloud disappeared after two days, and spend awoke after nearly 36 hours unconscious. In order to prevent a repetition of such disasters, in the reservoir tube are embedded which extract the carbon dioxide from its bottom. About six years, the villagers lived in fear that the existing pipes can not extract enough gas from the bottom of the lake are built two more.