How my brother's accident saved lives

Growing up in rural Guatemala, Marco Tulio Guerra was accustomed to people cooking using open-fire stoves. It's dangerous because of both smoke inhalation and the flames. But it was when his younger brother was in a horrible accident, that Marco decided to do something about the health hazards of the fires. He's designed a stove, which is safer for the billions of people who cook using this method. (Picture credit: M T Guerra.)