Officials are just beginning to assess the blast damage in the port warehouse district of Beirut, Lebanon following the devastating explosions earlier this week. The explosion was felt in Cyprus, 150 miles away. While the cause of the explosion is still unconfirmed, Lebanon’s interior minister has reported that 2,750 metric tons of ammonium nitrate likely caused the Beirut blast. It is clear, however, that the scale of destruction is massive with more than 135 people killed and another 5,000 injured in the explosion. Authorities declared Beirut a “disaster city” and imposed a state of emergency.
The event will likely draw comparisons between the West Fertilizer Plant explosion in 2013 and the 2015 warehouse disaster in Tianjin. Similar to the Beirut event, these events also involved ammonium nitrate explosions and caused large-scale destruction.
What Makes Ammonium Nitrate Explode?
Primarily used as a fertilizer and as a feedstock for commercial explosives, ammonium nitrate is also a powerful oxidizer and a rich source of nitrate, making it an explosion hazard. The storage of the chemical can increase or decrease its sensitivity to fire. To turn ammonium nitrate from a stable compound into an explosive, without any fuel or external catalyst, specific circumstances are needed. For instance, if the ammonium nitrate is exposed to combustible materials, it can quickly accelerate their flammability. It can also undergo explosive decomposition when heated in a confined space.
How Can Another Ammonium Nitrate Explosion Be Prevented?
After the West Fertilizer Plant explosion, the NFPA 400, Hazardous Materials Code, underwent some rigorous updates. The latest version called for new ammonium nitrate storage facilities to be of non-combustible construction, with separation of the material from contaminants, as well as automatic fire sprinklers and a one-hour fire barrier floor to roof required. They also imposed additional safeguards when a facility exceeds 1,000 pounds.
To meet these requirements, the first step is to understand whether you are over the maximum allowable limits of a chemical, such as ammonium nitrate, by taking an inventory of all the chemicals stored in your building. Knowing the hazardous materials in storage and in use is a prerequisite to identifying the hazards present in your facility and mitigating the risks to your employees and the public. Once the materials and their hazard classes are known, the thresholds for various building and process protection systems, such as fire sprinklers, ventilation and secondary containment, and subsequently personal protective equipment (PPE) needs, can be determined and applied.
Whether dealing with a new or existing building, there are valuable lessons to be learned from the Beirut ammonium nitrate explosion. The most important of them all is to understand the nature of chemicals stored in your building and to make sure your building is properly designed for the hazards those chemicals can create. HazAdvisr is a cost-effective hazardous material inventory database and design platform that can establish whether your facility is safe and compliant. With our team of engineering experts, we can help design safety measures appropriate to your facility to prevent an explosion from occurring.