Those who live in the world of Process Safety know all about “Line Break/Process Opening” and the lack of OSHA guidance or a standard to control this highly hazardous task. So I try to educate all that will listen by sharing “lessons learned” from previous incidents. This post is an attempt to show that although there is no 1910 standard covering this task, it does not slow down OSHA from issuing citations…
Accident: 302321138 – Three Employees Killed And One Injured In Fire
Accident: 302321138 — Report ID: 0418300 —
Event Date: 05/11/1999
SIC 302321138 05/11/1999 3089
Four employees were engaged in finding a polymer plug that would occasionally occur due to polymerization in the line. They had performed a line break and had reassembled the line, and then opened a tetrafluoroethylene (TFE) valve at a silica gel tower. This allowed full pressure on the line. Due to a poorly connected flange, air had been introduced into the line after reassembly and when the TFE came into contact with the air a fire resulted leading to an explosion of the tower. Two of the four employees were unable to escape the fire, and two others escaped the fire scene. However, only one of the two employees that escaped survived and was hospitalized with burns.
Employee #1 – Fatality Burn/Scald(Heat)
Employee #2 – Fatality Burn/Scald(Heat)
Employee #3 – Fatality Burn/Scald(Heat)
Employee #4 – Hospitalized injury Burn/Scald(Heat)
Accident: 200801611 – Two Employees Are Burned In Weak Black Liquor Release
Report ID: 0523300
Event Date: 05/30/2006
Between 10:30 and 11:00 a.m. May 30, 2006, Employees #1 and #2, who were maintenance workers, were working in the pump room, removing the pump for the weak black liquor storage tank. This activity required group lockout procedures. Procedures were not developed to identify the specific responsibilities for group lockout. The operators issue the line-breaking permits to the maintenance workers performing the task. The operators are tasked with closing specific valves in this line for this task. Lockout of the main circuit for the weak black liquor pump was done by Employees #1 and #2. The line breaking permit was issued by the operations department, who was at the time of the request working on an evaporator pump. Operations issued the line-break permit without closing the valves because they were “pressed for time.” Operations filled out the permit with the intent of coming back in what he thought would be a couple minutes to close the valves for which he was responsible. He did not expect that the maintenance workers would start as soon as they had. The operations department was responsible for closing the valve on the suction side of the pump. This valve was not closed which resulted in the release of the weak black liquor. Employees #1 and #2 checked the bleed off valve for the pump and nothing came out. One employee noticed that the bleed off valve was caked with dried weak liquor. He attempted boring it with a wire brush and still no solvent came out. The gate valves were checked by turning the handles and they did not move which indicated that they were in the ‘open’ position. One employee stated that the valve on the suction side was not seen, when he checked the other valves. Employees #1 and #2 began removing the bolts from the pump once the coupler was removed. All but four bolts were removed as a matter of practice. The last four bolts were loosened, and Employees #1 and #2 began prying the pump away from the volute, when the weak black liquor was released. Both employees ran out the door to the showers as the release occurred. Employees #1 and #2 sustained chemical burns and were hospitalized.
Employee #1 Hospitalized injury, Burn(Chemical)
Employee #2 Hospitalized injury, Burn(Chemical)
Accident 14406912 – Employee Killed When Exposed To Caustic Acid-Soluble Oil
At approximately 8:00 p.m. on July 16, 1994, Employee #1, an operator in the alky unit of an oil refinery, was between the acid regeneration system and the neutralization system. The level in the rerun tower (part of the acid regeneration system) was controlled by an automatic level control valve (92LC0102), which allowed the stream to flow to the ASO neutralization system. A line break at a T just past this control valve occurred while Employee #1 was trying to remove a bull plug from a 3/4 in. bleeder pipe. Employee #1 told the stillman that he was trying to correct a blockage in the line. The method he was using was not a normal method commonly used by the operators interviewed, and according to the alky unit operators, the operation that Employee #1 was performing did not have written operating procedures. The bleeder pipe that broke from the T was approximately 17 in. long with the Durco valve about 4 in. from the break and about 10 in. from the break to another T containing a bull plug. Another bull plug was also on the end of the bleeder. The P and IDs did not show this configuration for this bleeder. Employee #1 was exposed to acid-soluble oil or ASO, which contains 5 to 20 percent HF. He suffered chemical burns and was killed.
Employee #1 – Fatality Burn(Chemical)
Accident: 201921491 – One Employee Died, Four Injured In Flash Fire
On November 28, 1999, a blockage occurred in the South Teal Unit. The blockage or plug occurred somewhere in the recycle waste line on the second level of South Teal. 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 detail was also plugged. The system was isolated and a lockout/tagout permit was obtained. In order to unplug the detail, Employee #1 had to bolt a packing gland (which had a rod to push the plug through) and clear the plug from the detail. Then he tried the 150 pound nitrogen through the detail again. The nitrogen was able to move through the line back toward the control valve. 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 from the detail to the tank, 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 with plans to use the packing gland again. 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 Kellogg Brown and Root 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.
Employee #1 – Non Hospitalized injury Burn(Chemical)
Employee #2 – Non Hospitalized injury Burn(Chemical)
Employee #3 – Fatality Burn(Chemical)
Employee #4 – Hospitalized injury Burn(Chemical)
Employee #5 – Non Hospitalized injury Burn(Chemical)