Trendspotting: Five Years of Incident Report Data from the CSB

“It doesn’t take many observations to think you’ve spotted a trend, and it’s probably not a trend at all.”  — Daniel Kahneman

In a December 2022 press release, CSB Chairperson Steve Owens alerted us all to a worrisome spike in CSB-reportable incidents at chemical facilities and the need to focus on winterization to prevent major chemical accidents. We wondered at the time if the December 2022 spike (18 incidents, vs. 9 incidents in a typical month) was a harbinger of things to come.

Now, with a full five years of reports, it is clear that December 2022 was an outlier. Noteworthy, but not part of a trend. What is also clear is that for the first year of the CSB’s requirement to report significant incidents—those resulting in one or more fatalities, one or more in-patient hospitalizations, or property damage in excess of $1,000,000—incidents were underreported. Which is what the Chemical Safety Board expected.  In the subsequent four years, the average number of incidents has been about nine incidents per month, summer or winter.

(Note: For those that care, this data follows a Poisson distribution, with a 95% confidence interval of 4.0 to 17.1.)

What does another 2½ years of data tell us about CSB-reportable incidents?

Where Have Incidents Occurred?

Through the first five years of reporting to the CSB, there have been 497 incidents (which includes two incidents at the Limetree Bay Refinery in the U.S. Virgin Islands). The states can be ranked by their number of incidents. The usual suspects are in the top 10, but there are also surprises:

Those who are familiar with the chemical industry are probably not surprised to see Texas and Louisiana as the top two, which they have been every time the CSB issues a new compilation of data. Together, Texas and Louisiana account for 38 percent of all CSB-reportable incidents.

But Isn’t That Where the Chemical Industry Is?

It may be tempting to look at the rankings and shrug. After all, wouldn’t you expect more incidents where there are more chemical production facilities? Certainly. Each year until recently, the American Chemistry Council (ACC) compiled a Guide to the Business of Chemistry. Among many other statistics, the guide lists the number of chemical establishments in each state (p.100). The number of establishments shifts from year to year, but there is a good sense of relative incident rates to be gleaned from the data in the 2023 guide.

Overall, for all fifty states, the number of CSB-reportable incidents is 44 incidents per 1000 chemical establishments. Looking at the number per establishment changes the perspective, as demonstrated by the rankings in the table below:

Except for Texas and Louisiana, the states on this list only have a few dozen chemical establishments. Only four of the states on the original top-ten list remain: New Mexico, Louisiana, Arkansas, and Texas. Astonishingly, North Dakota proves to have the highest rate of incidents per establishment of any state in the country.

Maybe it’s not the number of establishments that matter.

Maybe It’s the Size of the Industry That Matters

Fortunately, the ACC Guide also compiles the volume of chemical production by state. (pp. 96-97)  It’s easy enough to divide the number of incidents by the volume produced. Looking at the average number of incidents per year divided by the value of the annual chemical production, we find that overall, it is 0.169 incidents per $billion shipped.

How does that change the rankings?

These ten states only average about $2.3 billion in annual chemical shipments. Texas, on the other hand, averages about $143 billion in annual chemical shipments and ranks 26 with 0.165 incidents per $billion shipped—slightly less than the overall average. Louisiana also dropped in the rankings. With $65 billion in annual chemical shipments and a rate of 0.215 incidents per $billion shipped, Louisiana ranks 19.

Where Incidents Haven’t Occurred

When Valero reported the first incident, on April 10, 2020, at its Meraux Refinery, Louisiana had the distinction of being the only state that was home to a CSB-reportable incident. The other 49 states were incident free. Louisiana held that dubious honor until less than a week later, on April 15, when Maine became the second state to have a CSB-reportable incident. After 19 months of reporting, only 14 states were free of CSB-reportable incidents. After 25 months of reporting, the list was down to 10 states free of CSB-reportable incidents.

Now, after five full years of reporting, we are down to just six states from which no significant incident has been reported to the CSB. While there is not a lot of chemical industry in these states, they each have some:

Consider Alaska and North Dakota. Each has 15 establishments in the chemical enterprise. Alaska has had no incidents in the last five years; North Dakota has had nine. Then there is Oregon, with 184 establishments, which exceeds the number in 28 other states. Yet 23 of those states have had CSB-reportable incidents, including New Mexico, with 14 incidents in 35 establishments, and Arkansas, with 13 incidents in 87 establishments.

So, it’s not just the number of establishments that drive the number of incidents. They are doing things right in some states, and we need to learn from them.

What Can We Learn? And Where?

There are two states that make every top-ten list, no matter how the data gets sorted. They are not Texas and Louisiana; they are New Mexico and Arkansas. If we want to understand what is going wrong in the chemical industry, they are the state that should get our attention.

But it is probably not the states that are doing badly in terms of CSB-reportable incidents that deserve our attention, but the states that have consistently done well. What can we learn from the chemical industry in Oregon? In New England? What is it that they are doing right?