May 16, 2011 | Mark Paradies

Monday Accident and Lessons Learned: The Difference Between Nuclear Incidents and Incidents in Other Industries

The nuclear industry is often cited as an example of a high-reliability operations or operational excellence. Being a nuclear engineer who works across many industries, I often get asked to compare the seriousness of incidents in various industries to the nuclear industry. A recent incident at a TVA reactor in northern Alabama points to the differences I see.

It seems that during a plant shutdown, it was found that a valve on a safety system did not open when it received the signal to open. The Nuclear Regulatory Commission rated this failure as a “red” failure – the most serious for an incident. As a result, the NRC decided it would increase inspections and oversight at the three reactor plant beyond the two full-time NRC resident inspectors that every nuclear plant has.

From the press reports, I found the valve was not a single failure point in the system. There was redundancy. Also, the value had worked properly during a prior tornado that occurred in northern Alabama. And it had worked when it was tested in the previous outage.

The article in The Wall Street Journal said:

“The NRC said with the system not working, the reactor core could have been damaged ‘had an accident involving a series of unlikely events occurred.’ A damaged reactor core can lead to the release of dangerous radiation.”

What this means is that with a failure of the normal systems and with a failure of the other redundant systems, if none of the valves could be opened manually, the core could have overheated. This would put us into a condition where core damage (melting) could occur. But that still doesn’t cause a containment breach, and no one receives any significant immediate radiation dose.

Yet, this is rated as red – the most serious incident.

Now compare this to other industries. Here are some examples from recent history …

Refining: BP Texas City Refinery explosion caused 15 deaths, the destruction of an operating asset, environmental airborne and ground releases of hazardous materials, damage to surrounding property, and billions of dollars of compensation and lost production.

Oil Exploration and Production: BP/Transocean Deepwater Horizon caused 11 fatalities, injuries to many employees, the loss of Transocean’s drilling rig, perhaps the biggest oil spill in history, over $20 billion in losses and compensation by BP, the shut down of oil drilling in all US waters for almost a year, and a whole new set of regulations that will make drilling more difficult for every offshore oil operator no matter the risk of their operations.

Mining: Upper Big Branch Mine explosion caused 29 fatalities, and the whole company was eventually sold.

Hospitals: Everyday fatalities occur due to human errors. Estimates are that 100,000 people per year die in the US due to “sentinel events” in healthcare facilities. The cost of healthcare errors in the US is estimated to be $17 Billion. But these accidents happen one person at a time. Examples of these accidents are all too common.

Do you notice any difference? The NRC is focused on preventing system failures that could lead to bigger failures that could lead to a process safety “disaster” that could cause a release of radioactive material.

The other industries have real fatalities.

Even the Fukushima disaster – a failure caused by a natural disaster – has not caused a fatality (even though perhaps up to 20,000 people lost their lives in the historical earthquake and tsunami that preceded the core meltdown).

I tell my kids (who are in college) … To get A’s in college, you don’t aim to get the minimum A. You don’t aim to get “good grades.” You aim to be at the top of your class. Nobody has a higher grade or tries harder than you.