On August 4, 2020, a large amount of ammonium nitrate stored at the Port of Beirut in Lebanon accidentally exploded, killing more than 200 people, injuring over 6,000 and causing miles worth of structural damage. Various buildings such as residential areas, commercial centers, hospitals, and schools were damaged, leaving an extensive economic burden in addition to the injuries. The port was storing 2,700 tons of ammonium nitrate, when a fire broke out in an adjacent warehouse. It is believed that the heat from the fire detonated the stored ammonium nitrate, causing the massive blast, with catastrophic consequences to the country of Lebanon.
The Beirut explosion may be one of the most devastating blasts in recent history, however it is not an unheard-of event. There have been numerous explosions involving ammonium nitrate around the world. In 1947, an ammonium nitrate explosion in Texas City, TX killed 581 people and injured thousands more. In this case, longshoremen had spent five days loading sacks of ammonium nitrate onto a ship. At least 2,300 tons had been loaded when workmen who boarded it noticed a fire. By the time the town’s firefighters arrived, a cloud of dense and colorful smoke had attracted bystanders. Then, the ammonium nitrate cargo detonated in a blast so powerful it shook the ground for hundreds of miles and led to a 15-foot wave that crashed over the dock and flooded surrounding streets. As recently as 2013, an intentionally set fire caused an explosion involving Ammonium Nitrate at the West Fertilizer Company. This explosion was in the small town of West, TX, killing 15 people, injuring more than 260 and damaging hundreds of homes.
Ammonium nitrate (NH4NO3) is a white/gray crystalline solid, which is commonly used in agriculture as fertilizer, as well as a component in explosives utilized in mining and construction operations.
Under normal and safe conditions, the chemical is highly stable. However, it can explode after exposure to heat, along with contaminants, which set off a cascade of reactions. This cascade also requires pressure to build up in a confined space, without being able to dissipate. Burning ammonium nitrate in an open field, for instance, is not likely to result in an explosion. Storing bulk ammonium nitrate over time can result in the material hardening, which makes the explosive force much more devastating.
As was seen in all three of the incidents above, the “initial” event was typically a fire in nearby materials, exposing the ammonium nitrate to the heat needed to begin the cascading decomposition process. Safe storage and transportation procedures urgently need to be implemented for companies storing hazardous materials.
This underscores the criticality of having precautions, such as Hot Work Permit programs, to prevent a fire from starting in ordinary combustibles which could expose hazardous chemicals, ignitable liquids, or combustible dusts, resulting in a much larger event.
If you would like a review of storage practices conducted at your facility, please contact Risk Logic. We will work with you to determine acceptable options and alternatives to keep your workplace safe.
Al-Hajj S, Dhaini HR, Mondello S, Kaafarani H, Kobeissy F and DePalma RG (2021) Beirut Ammonium Nitrate Blast: Analysis, Review, and Recommendations. Front. Public Health 9:657996. doi: 10.3389/fpubh.2021.657996