A huge explosion in the warehouse area of Beirut killed at least 135 people and injured nearly 5,000. Lebanese President Michel Aoun said that 2750 tons of ammonium nitrate had been stored in the port for six years without safety measures.
Below are details about ammonium nitrate and expert comments.
* Ammonium nitrate is an industrial chemical commonly used in the manufacture of fertilizers and used as explosives in quarries and mines. It is considered a relatively safe material if it is far from pollution and has been properly stored. But they are extremely dangerous if they are contaminated, mixed with gasoline or stored unsafe.
Exposure of a large amount of ammonium nitrate to intense heat can cause an explosion. Storing them near large fuel tanks in large quantities and in a poorly ventilated facility can cause a massive explosion. The larger the quantity, the more likely it is to explode.
"This explosion is classified as less than a nuclear bomb and stronger than a conventional bomb. This is perhaps one of the largest non-nuclear explosions over time," said Ronald Alford, general manager of Alford Technologies, a British company that specializes in eliminating explosive materials.
* Experts note that the color of smoke and the "mushroom cloud" seen in the video footage of Tuesday's explosion are characteristic of ammonium nitrate explosions.
"The video footage of the accident initially showed white and gray smoke, followed by an explosion that released a huge cloud of brownish-red smoke and a large white fungus cloud. This indicates that the gases emitted are ammonium nitrate fumes," said Stuart Walker, of the University of Flinders' College of Criminal, Environmental and Analytical Chemistry. White, red nitric oxide, brown toxic and water. "
"If you are making explosives of ammonium nitrate, you should not show this brown cloud with you. Their appearance means that the rate of oxygen is incorrect, so it is not mixed with explosives. The Beirut explosion appears to be an accident, unless it is intentional."
Previous incidents
Here are some of the bloodiest industrial accidents in the world due to explosions caused by ammonium nitrate:
* In 1921 an explosion of a sulfate compound and ammonium nitrate fertilizer in the Obau factory in Germany killed 565 people.
* In 1947 a fire caused the explosion of 2,300 tons of a chemical substance on a ship in the port of Texas, in the United States of America, causing a tsunami. At least 567 people were killed and more than 5,000 injured.
* In 2001, an explosion at an ammonium nitrate store in Toulouse, France, killed 31 people and injured 2,500.
* In 2013 an ammonium nitrate explosion stored in a Texas fertilizer plant killed 14 people and injured about 200.
* In 2015, explosions at a warehouse used to store ammonium nitrate and other chemicals in the port of Tianjin, China, killed at least 116 people.
"The idea that such a quantity was left unattended for a period of six years that is hard to believe, was a time bomb," said Andrea Sella, a professor of inorganic chemistry at the University of California, Los Angeles, on the Beirut explosion.
Use in making bombs
Ammonium nitrate can be mixed with other materials to make a bomb. It was used in the IRA bombings in London in the 1990s, as well as in the 1995 bombing of a federal building in Oklahoma City, America, in which 168 people were killed, and in the 2002 bombings of nightclubs in Bali, Indonesia, in which more than 200 people were killed. Many ammonium or homemade bombs that were used against US forces in Afghanistan also contained ammonium nitrate.