Damaged buildings near the Houston explosion

People living in northwest Houston were awakened early Friday morning, January 24, by a tremendous explosion. A dramatic doorbell-camera video taken from a nearby neighbourhood shows a brilliant flash followed by a rising fireball, and then the camera is knocked off its mountings by the arriving shock wave.

The explosion demolished much of Watson Grinding and Manufacturing, killed two workers, injured about 20 people, and damaged some 400 homes and other structures nearby, 35 of them seriously.

Investigators from the US Bureau of Alcohol, Tobacco, and Firearms determined that the cause was likely a spark that set off propylene gas leaking from a 2,000-gallon tank, which was later secured by HazMat crews. The family of one man killed in the explosion has filed a wrongful-death lawsuit, and Harris County has filed suit on behalf of its residents because it claims the firm failed to exercise due care to protect the public.

Chemical explosions and fires are nothing new to the residents of Greater Houston and the coastal region near it, which has one of the largest concentrations of refineries and petrochemical plants in the world. The things you can make by tormenting hydrocarbons and other materials with extreme heat and pressure are valuable to the world's economy, and so a lot of money goes into building plants and equipment that necessarily involve dangerous materials and processes.

At this point it is rather speculative to ask what Watson Grinding and Manufacturing was doing with all that propylene. The most likely answer is that they were using it as a substitute for the even more hazardous acetylene in welding operations and other applications requiring lots of gas-fuelled heat, such as heat treating. Propylene is a gas at room temperature, but like other light hydrocarbon compounds, it can be compressed into liquid form, and that is probably how it was stored in the tank.

One news report points out that any facility where more than 10,000 pounds of propylene are stored has to conform to certain reporting requirements, which Watson Grinding and Manufacturing apparently failed to do. By my calculations, 2000 gallons of the stuff weighs just about exactly 10,000 pounds, so they may have squeaked under the wire on this one. Regardless of such reporting, it's obvious that not only did a serious propylene leak occur, no alarms were set off by gas-leak detectors, which these days are not that expensive. The two employees killed were in the facility's gym, exercising before a work day they never had.

Did these men, who were probably glad to have reasonably well-paying manufacturing jobs, deserve to die? I can't imagine anyone saying “Yes” to that. Yet they knew, or may have known, that the stuff they were working with was dangerous, and now and then things go wrong even in the best-run facilities. A society can be judged by the way it deals with clear cases of injustice, and many industrial accidents fall into that category.

The people who own and/or operate the facility rarely spend much time on the shop floor, exposed to the hazards that they have created. The people who are injured are killed are either low-level operatives or sometimes just innocent bystanders who could afford only the kind of housing you find in the vicinity of manufacturing districts. The days when factory owners would build a mansion next door to the plant are long gone.

We don't have to imagine an alternative universe where regulations on manufacturing would be so tight that hardly anyone, down to the lowliest worker, would be at risk of injury or death. We have only to look to places such as Amherst, Massachusetts, where I worked for many years. The regulatory and civic environment was such that anyone wanting to run a plant offering hazards more serious than a paper cut had to flee to another location, such as Sunderland or Hadley. If some dictator (I won't say anything about the current candidates for presidential nominations) managed to implement Massachusetts-style federal regulations on the whole country, including Houston, why, Houston would be a much safer place to be. It would also turn into a ghost town, or large sections of it would, because the thing that has already happened to a great deal of manufacturing activity in the US might well happen to the petrochemical and refining industries and all their ancillary commercial infrastructure as well: it would move offshore to places less hostile to hazardous commercial activity.

This is not to set up a false two-way choice between prosperity and death for workers on the one hand, and third-world poverty and safety on the other hand. There is a third way, one that allows for dangerous manufacturing processes, but with due attention paid to the hazards involved.

To their credit, most of the firms doing hazardous manufacturing manage to keep their workers reasonably safe most of the time. If factories blew up every day, it wouldn't be news. Still, every explosion reveals a failure of attention: attention to what might go wrong and diligence in stopping it from going wrong before it gets too far.

In the coming months, investigators and lawyers will find out a lot about how Watson Grinding and Manufacturing dealt with these problems. The most important “machinery” in a plant is invisible: it's the network of minds and human relations that keep the place going while enforcing a culture of safety and backing up that culture with needed resources—or not, as the case may be.

It's obvious that something went wrong: a leak that began small got bigger, a leak detector that should have sounded the alarm was malfunctioning or not purchased in the first place, and an unfortunate combination of circumstances culminated in the tragedy caught on the doorbell camera.

The word “love” is rarely brought up in discussions of engineering ethics, but in the proper context, it provides the foundation for good corporate and industrial behaviour. Here's a question that those in charge at Watson could ask themselves. Take someone you love—a son, daughter, spouse—and answer this question: would you want your beloved to work at any job in your plant? For years? If not, why not? The answer to those questions can motivate improvements that could prevent things like the explosion at Watson Grinding and Manufacturing in the future. But only if they are asked, and answered in the right way, with actions as well as words.

Karl D. Stephan is a professor of electrical engineering at Texas State University in San Marcos, Texas. This article has been republished, with permission, from his blog Engineering Ethics, which is a MercatorNet partner site. His ebook Ethical and Otherwise: Engineering In the Headlines is available in Kindle format and also in the iTunes store. 

Karl D. Stephan received the B. S. in Engineering from the California Institute of Technology in 1976. Following a year of graduate study at Cornell, he received the Master of Engineering degree in 1977...