AN OIL ACCIDENT

It was not the purpose of this month's editorial to scare people in Long Island with oil fires, but to point out the callous politics of hysteria about nuclear accidents while ignoring dangers that are thousands of times greater in both probability and consequence. Though oil is very much more dangerous than nuclear, it is nothing to panic about, and left alone by the media, people don't.

On the other hand, oil and its production cycle is not as harmless as is often thought. In July 1984, a steel tank exploded at the Union Oil Company's Chicago refinery, leaving 17 workers dead, 17 injured and $100 million in property damage. The 40-foot, 20-ton vessel took off like a rocket by the sudden vaporization of the liquid inside, and landed more than half a mile away, knocking down an electric power transmission tower and making a crater 12 ft deep and 20 ft across.

To investigate the disaster, OSHA called in the Dept. of Commerces National Bureau of Standards, which recently published its report. The vessel material met or exceeded specifications, the welds were stronger than the base metal, and the 16 year old tank had been inspected regularly every 2 years since installation. Hydrogen embrittles metal and causes it to crack, so whenever such beginning cracks were detected, they were repaired by welding, or the entire circumferential segment was replaced and welded to the old body.

But the metal near the repair welds hardened and became even more brittle. The final fracture causing the disaster occurred near a repair weld and tore the vessel open like a zip. The cure: preheating and post-weld heat treatment; and low-hydrogen welding using oven-dried electrodes.

As readers know, an analogous embrittlement of metal occurs in nuclear plants by high neutron flux rather than hydrogen. Much care has always been given to vessels and pipes exposed to high neutron flux, and where cracks did occur, they resulted in enormous publicity. Why did the Chicago disaster make few headlines and no lasting impression?

Because those 17 people were torn apart, burned or crushed to death: tragic, but understandable. What made it of no interest to the media morons is the lack of what to them is the unfathomable mystery of radioactivity.

[More: US Dept. Commerce news release 9/22/86; NBS report NBSIR-86- 3049; $22.95 from NTIS, Springfield, VA 22161, order no. 86-226594/AS.]