Tianjin: 31 Seconds Between Two Explosions

Thirty-one seconds. That was the time between the first explosion in this port and the second. Remember that number. The second was the big one: about 430 tonnes of TNT, by the official investigation. It left a crater ninety-seven metres wide. By the next morning, smoke from the fires could be seen from space. In that yard sat 800 tonnes of ammonium nitrate, where China's own port rules allowed none. So why was it there, a few hundred metres from people's homes? And why could no one at the yard tell the firefighters what was burning?

The company behind this yard was less than three years old. On the night of the fire, its warehouse held more than a hundred kinds of dangerous goods. Tianjin lies about a hundred and twenty kilometres from Beijing. Its port district, Binhai, is a landscape of container yards, warehouses and lots full of new cars. Ruihai International Logistics was a private company. Its site covered about forty-six thousand square metres. On its north-west side was a fenced customs area, where export containers waited to be cleared and loaded onto ships. In all: 111 kinds, more than eleven thousand tonnes. Among them were 800 tonnes of ammonium nitrate, about 680 tonnes of sodium cyanide, and more than two hundred tonnes of nitrocellulose and related products. The report's own tables give their classes. Nitrocellulose: class 4.1, a flammable solid. Ammonium nitrate: class 5.1, an oxidizer, which can feed a fire with oxygen. Sodium cyanide: class 6.1, toxic. Fuel, oxygen and poison, in the same yard. And about twenty metres from where the first explosion would happen sat another group of containers, with more ammonium nitrate. Keep that in mind.

For a total of eleven months, this yard handled dangerous goods with no licence and no approval at all. Ruihai began handling dangerous goods in May 2013, while still building a yard it had started without the required permits. Its full port licence for dangerous goods came on June 23rd, 2015, about seven weeks before the fire. How did it get its approvals? The report describes cash, gift cards, golf and dinners for port officials. In 2016, a court convicted the company's chairman of crimes that included bribery. The report also found falsified safety assessments, and a yard design that put ammonium nitrate and sodium cyanide in open stacks, against national rules. By 2015, the yard moved more than fourteen times its approved volume. Its sodium cyanide stocks stood at about forty times the design limit.

China's own port standard had a short rule for ammonium nitrate: it does not stay in the port. Containers of ammonium nitrate, and of explosives of divisions 1.1 and 1.2, go straight from truck to ship, or from ship to truck. On the night of the fire, Ruihai had 800 tonnes of it sitting in the customs area. The same standard limits the stacks. Containers of flammable or explosive goods: two high at most. Other dangerous goods: three. At Ruihai, the report found stacks four and even five high, different classes mixed together, and far too little space between them. At sea, the IMDG Code, the rulebook for dangerous goods on ships, sets segregation rules. In its table, a class 4.1 flammable solid and a class 5.1 oxidizer must be stowed at least "away from" each other. As a rule, they may not share a container. There was a rule for distance, too. A large hazardous chemicals warehouse had to stand at least one thousand metres from public buildings and main roads, and away from homes. The report found Ruihai did not meet the safety distance to the housing estates, or to the port fire brigade's own office. Satellite measurements by Greenpeace and by the press put the nearest homes about three hundred to six hundred metres away.

Investigators ruled out sabotage, lightning, wiring and any flame from outside the containers. The cargo lit itself. They screened all seventy-two kinds of cargo in the customs area. Only one could heat itself to ignition. They also set fire to a forty-kilogram drum of it in a test, and compared the flames with security video. They matched: nitrocellulose. Nitrocellulose, used in lacquers, has poor chemical stability: even at room temperature, it slowly breaks down and gives off heat. That is why it is usually wetted, with alcohol or water. Without that wetting agent, the report says, it catches fire very easily. The suppliers packed it by hand, in plastic bags that were not heat-sealed, just tied with string, inside paper drums. Workers told investigators that packages had broken during loading. The report also found drums tipped off forklifts and rolled by hand. In tests, a broken package at fifty degrees lost all its alcohol in two hours. August 12th was hot, with a high of thirty-six degrees Celsius. Experiments showed that at thirty-five degrees outside, the inside of a container passed sixty-five. Dry nitrocellulose heats itself faster from about forty. A closed steel box holds that heat in, until the cargo ignites on its own. That is the lesson for anyone who handles it. Packaging, heat and time are part of the hazard.

The first fire crew reached the yard four minutes after the alarm. Their station was just across the road. The commander asked the warehouse staff what was burning. None of them knew. Containers blocked the lanes, and a crane could not clear them. So the firefighters cooled the stacks next to the fire, and then the heat forced them back. In all, thirty-six fire engines and two hundred personnel were sent. They evacuated more than a hundred workers and neighbours, and sprayed water and foam on the containers from outside the customs area. The report says they had no clear picture of which chemicals were stored, or how much. Inside the customs area, the fire was spreading toward the ammonium nitrate.

In tests, burning nitrocellulose passed a thousand degrees after half an hour. The report gives the thresholds for ammonium nitrate: it starts to decompose at 110 degrees, and above 400 it decomposes violently and explodes. At 11:34 and six seconds came the first explosion: about fifteen tonnes of TNT, by the report's estimate. Remember the thirty-one seconds? About twenty metres from the first blast sat more containers, with ammonium nitrate, potassium nitrate, other oxidizers, flammable solids and corrosives. The spreading fire and the shock wave of the first blast, the report says, set off the second. At 11:34 and thirty-seven seconds came the second explosion. The report put that blast at about 430 tonnes of TNT. Around the main crater, buildings within a hundred and fifty metres were destroyed. A tank container was thrown into the fourth floor of an office building. Thirty fire engines were lost. More than twelve thousand new cars in the nearby lots, and seven and a half thousand containers, were damaged or destroyed. Severe damage reached about two and a half to three and a half kilometres out, depending on direction. Windows were damaged more than eight kilometres away. The flames were not put out until the afternoon of August 14th.

The official count: 165 people died, and eight were listed as missing. Most of the dead were people who came to help. Ninety-nine were firefighters, seventy-five of them from the port's own fire service. Eleven were police officers. Fifty-five were workers and people who lived nearby. Another 798 were treated in hospital. Behind every one of these numbers is a person, and a family. Large amounts of sodium cyanide were scattered across the site. The report found no case of anyone poisoned or killed by the pollution. More than thirty thousand people were affected, and the direct losses were put at nearly 6.9 billion yuan.

So what did the investigation conclude? The report's verdict: an especially serious work-safety accident, one for which people were responsible. It was not sabotage. The company had stored and handled dangerous goods illegally, with safety management the report called extremely chaotic. Its managers, operators and dock workers did not know what was in the customs area, how much, or how it behaved. The port fire brigade had visited Ruihai many times, but had never entered the customs area. It had no plans for the different chemicals it might face. The report blamed others too, from the port officials who licensed the yard to the consultants who signed off its safety assessments. Criminal cases were opened against forty-nine people. It proposed discipline for seventy-four more. In November 2016, courts sentenced forty-nine people, twenty-five of them officials. Look at the chain. A cargo that had to stay wet, packed in bags tied with string. A yard that stacked classes together, far too high. Ammonium nitrate where the rules said it could not be. And firefighters who arrived without knowing what was there.

Days after the blast, China's State Council ordered a nationwide inspection of businesses using dangerous chemicals and explosives. Within weeks, local governments had sent plans to move about a thousand chemical plants away from populated areas. The report asked for more. Dedicated zones for dangerous goods in ports, with storage by type and a strict cap on how much passes through. Rules in law for packing and moving nitrocellulose. A single national database of dangerous chemicals, shared with the fire services. And strict distances from the places where people live. Almost five years later, a warehouse of ammonium nitrate exploded in Beirut. China's State Council safety commission and emergency management ministry ordered ports, docks, logistics warehouses and chemical parks inspected again, and singled out ammonium nitrate.

Tianjin was not a ship, and not a voyage. It was a yard, where cargo waited. And that is where the hazard waited too. In a dried-out bag, a stack too high, a rule that was not enforced. And a fire crew that did not know what it was facing. Storage is part of the supply chain. On land, as at sea, the rules only work when someone enforces them. This is Hazard Manifest. If you want to understand the dangerous side of global trade, subscribe.