The largest man-made non-nuclear explosion in human history

Today we’re talking about the largest man-made non-nuclear explosion in human history.

What does that mean? That means we rule out natural explosions like meteorites hitting the Earth, and then we rule out various nuclear bomb tests, and the two bombs that the United States dropped on Japan. We are simply talking about a massive explosion caused by human error, which is the worst explosion in terms of the number of people killed and the power of the explosion, as well as the damage to property and international impact.


The story we tell today takes place in Halifax, Nova Scotia, in eastern Canada.

As you can see from the map, Halifax is a coastal city. And the greatest resource here is a very good natural harbor, but also the world’s few natural deep water port. Once this depth increases, it can dock larger ships, such as large cruise ships, warships, cargo ships, and so on. So at the end of the 19th century, around 1880, the Canadian government first built the railroad here, and then built a series of port facilities.

The government wanted to make Halifax an important import and export city, but later the domestic economy did not develop very well, it did not have so many competitive products to export to the world. So Halifax’s growth has been slow, and its population has remained at about 20,000. But with the outbreak of the First World War, Halifax finally came into its own.


In 1914, the First World War broke out. For the next four years, the war was fought mainly on the European continent. North America’s Canada and the United States naturally took over the logistics. A large number of merchant ships began to travel between Europe and North America. Halifax became almost a necessary route in the trade routes, and Halifax port became one of the busiest ports on the west coast of the Atlantic. Large quantities of goods were transported by rail to ports and then by merchant ships to all parts of Europe. Such as wood, coal, grain, ammunition and so on. At the same time, busy trade also created a wealth of jobs, sugar factories, clothing factories, repair shops, railway factories, restaurants, bars, schools, churches and trading companies mushroomed. The population of Halifax grew from 10,000 or 20,000 before the war to about 50,000 or 60,000, and these people worked and lived mainly around the port.

In 1917, the merchant ship Imoy, belonging to the Norwegian Company, first came to New York. Here they loaded up with various relief supplies, and then came to Halifax for loading fuel (coal) and neutrality checks. Adding fuel makes sense. Go where it’s cheap. This neutrality check means that Norway was a neutral country in World War I, so as a neutral country, you can send relief supplies to war zones, but you can’t send weapons and equipment. Canada acts as a third party inspection agency, and as long as the ships pass neutral inspection, they are relatively safe to sail.


On December 3, the merchant ship Imoy docked in Halifax harbor. The IMO was scheduled to leave port by the afternoon of December 5. But by evening, the harbor’s anti-submarine nets were up, and the fuel loading of the Imo was only just completed.

The anti-submarine net is actually a big net that surrounds all the entrances and exits of the harbor. The main purpose of this is to prevent submarines from sneaking in at night and wreaking havoc. During World War I, German submarines posed a great threat to the Allies. Especially the British Mediterranean fleet, which was cut off from trade routes in the Mediterranean, so important ports were equipped with anti-submarine nets.

Because of the delay in loading fuel, the IMO had no choice but to wait until the next day before loading anchor and leaving port. Meanwhile, the merchant ship Mont Blanc from France did not enter port in time before the anti-submarine net was raised. Then it would have to stay out of the harbor until the next day. The merchant ship Mont Blanc was also coming from New York, but instead of relief supplies, it was carrying barrels of dynamite and boxes of guns. Ships carrying dangerous chemicals were not allowed to enter Halifax harbour, but as the war became more intense and submarines moved out to sea more frequently, the port was much more relaxed than before the war.


At 7:30 a.m. on December 6, the anti-submarine net was opened, and ships could enter and leave port in a smooth sequence. As we can see from the map, the port of Halifax is like a pocket. It is connected to the Atlantic Ocean by a narrow passage. The rule was to keep to the starboard side of the port, just like driving on the right.

The first ship to enter the port was an American merchant ship, which was towed into the channel by a tugboat and then temporarily diverted to the west side of the channel, meaning it was occupying the outbound channel. Then the merchant ship Mont Blanc began to sail into port on the right side as normal. At the same time, the Imo was given the go-ahead to leave port. It had been delayed all night, so the captain of the Imo decided to speed through the narrow passage.

It’s the same as driving a car. My normal lane is occupied by an American merchant ship, so I have to use the other way. In this way, the merchantman Imoy and the merchantman Mont Blanc were sailing face to face. When the distance between the two ships was about 1.2 kilometers, the captain of the Mont Blanc noticed something unusual, so he made a brief noise. This brief noise meant that I had authorization and I was going to pass normally. But the Imo immediately answered with two short noises, which meant that I, too, would go on. The captain of the Mont Blanc was puzzled when he heard the noise. It was clear that you were in the wrong lane. But the captain stopped the power system, and the ship listed further to the right in an attempt to give the Imo a wider lane.


The captain of the Imo probably thought I could get through with a little more speed, but as the ship got closer to the Mont Blanc, something bad happened. At that speed and the width of the channel, it wouldn’t have made it through. So the Imo quickly reversed its engines and made an emergency turn.

But it was too late. The Emo crashed into the Mont Blanc at 2 kilometers per hour. Although the impact was not very strong, it caused the Mont Blanc to shake violently. The strong shaking caused the parabens on the deck to topple and break, and the flammable liquid began to flow through the deck to all corners of the warehouse. The heat and sparks from the impact ignited the paraben vapors, causing the fire.


The crew of the Mont Blanc initially tried to put out the fire, but thick black smoke soon spread to every corner of the ship. The crew feared that the fire would cause an explosion, so they quickly got into lifeboats and rowed to shore. The flames and plumes of black smoke attracted crowds of people who gathered near the shore to witness the rare sight.

The people at the time did not know that the Mont Blanc was carrying a ship full of dangerous chemicals. In fact, under normal circumstances, ships carrying dangerous chemicals are painted with bold symbols. But it was a time of war, and the warring nations did not want to expose their ammunition supply ships, so the Mont Blanc did not have hazardous chemicals on its hull. The crew was aware of the situation, and in the process they shouted to the people, the ship is going to explode, you need to get away from here.


Unfortunately, the crew spoke French, which was not understood by the people around them. So it was a scene of sailors fighting for their lives, firefighters fighting for their lives, people talking about it on the shore, and people looking up in the distance. The people of the city seemed to be watching the situation, unaware that the danger was creeping up on them. Twenty minutes after the collision, the Mont Blanc exploded violently.

At the moment of the explosion, the temperature in the center of the explosion reached 5,000 degrees Celsius. A powerful explosive wave traveled 200 kilometers at a speed of 1,000 meters per second and caused an 18-meter wave. Within a radius of two kilometers from the center of the blast, almost all the houses, factories and stations were flattened. The commercial ship Imo was blown ashore and its half-ton anchor was blown three kilometers.


The crowd of onlookers on the shore and the firemen who went deep into the fire died instantly, as did the crew of the Imo. The powerful shock wave shattered the Windows of the houses, and the glass shards plunged into the bodies of the people like bayonets. Among the onlookers, more than 40 were permanently blind and more than 5,900 suffered severe visual impairment. Because it was just after 9 a.m., and people in Halifax live around the harbor. So school students and factory workers were killed and injured when buildings collapsed.

Rescue efforts have also been difficult in the aftermath of the explosion. First of all, the government units are severely understaffed, most of the firefighters and some police were killed by the explosion. Secondly, people thought it was the Germans who had dropped some kind of bomb, so people were afraid to go out and do rescue work. Moreover, the railways and ports were badly damaged, making it difficult for people from outside to get in.


The day after the explosion, Halifax was snowed all day, with more than 40 centimeters of snow, which made rescue efforts extremely difficult. The disaster killed nearly 2,000 people, injured about 9,000, damaged 12,000 homes and left 6,000 homeless. Halifax’s factories were all but destroyed, cutting off the economy’s lifeline. Losses were estimated at about C $35 million at the time, and now total C $591 million, or about 3 billion renminbi.


These numbers make the Halifax explosion the largest man-made non-nuclear event in history.

Through this incident, I think I don’t need to say more, you should also know what caused the disaster. In our real life, they are illegal lane occupation, temporary lane overtaking, speeding in disregard of regulations, dangerous chemicals without marked signs, eating melons and watching plays. These problems are happening around us all the time, and I hope that we can play a certain role in warning our behavior through this incident. In this way, we can ride with the world of mortals, live a little guilty, sharing the prosperity of the world.

Post time: Sep-23-2022