December 1, 2022

LINE BREAKING INCIDENT

 On November 28, 1999, a blockage occurred somewhere in the recycle waste line on the second level. This line brings crude Teal with excess aluminum to T-103, which feeds back to the reactors. During the night shift they were able to blow the line from T-105 to the control valve, which left the blockage within about 20 feet of T-103. The morning of November 29, 1999, Employee #1, the outside operator, tried to blow out the plug through a detail (bleeder) just above T-103 with 150 pounds of nitrogen. 

The nitrogen pressure went around the control valve via a by-pass to the slop tank. He closed the valves back toward the slop tank. Then he opened the valve into T-103 to try and blow nitrogen into the tank, but it was still plugged somewhere, which was about 1 to 2 feet of line. At this point they were going to have to perform a line break and separate the line above the valve on T-103.  The line breaking permit was obtained. Employee #1 relieved the nitrogen pressure back to the slop tank, but the slop usually had 3 to 10 psig on it. He ensured that the valves were closed, locked and tagged. 

Then the maintenance crew came to perform the line break. The crew consisted of four employees, which all wore a hard hat with attached face shield, safety shoes, safety glasses, PVC gloves, nomex, and aluminized suits. Employee #1 stayed in the area, but over at the guard rail. The guard rail was just under 10 feet and was about 9.5 feet from the line break. He wore the same PPE except the face shield and aluminized suit. The maintenance crew proceeded to break the flange. One bolt was out and the other three were loose. The shift supervisor was standing on the ground level talking with the Employee #1. Employee #1 told him the flange started to drip. It started to spray lightly and then quickly just gave way into a stream. The stream hit Employee #2 in the face, because he was kneeling as he was working. Employee #1 saw the flames. As he was being burned by the fire, he jumped over the guard rail and fell approximately 12 feet to the ground. Employee #1 sustained a fractured ankle and compressed L1 vertebrate, and was killed. The flash fire lasted about 10 seconds according to the shift supervisor. Employee #2 was hospitalized for his burns. Three other employees were burned during the accident but didn't require hospitalization. 

Source:OSHA.GOV

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