Document 6RQeYRp3D12NKwEoMgw5Qr7jR

7 V) -V ,, INTEROFFICE MEMORANDUM Date: From: Dept; Tel NO: 25-Aug-1997 08:15am EDT JOHNSONS JOHNSONS@HNY@MRGATE@CLE TO: TO: TO: GRESSLER, J0HN@A1 HODSON, MIKEOAl FORBES, PAT@A1 Subject: INCIDENT OF EXPERIENCE - FOR YOUR INFORMATION & COMMENTS TO ALL, THIS EXPERIENCE OCCURRED DURING PLANT SHUTDOWN. NEVERTHELESS, IT SHOWS A BOOBY TRAP CAN BE PRESENT IN THESE TYPES OF REGULATORS. IF ANYONE HAS HAD A SIMILAR EXPERIENCE, PLEASE RESPOND. STAY SAFE, SCOTT JOHNSON From: To: CC: Subj: HNY::LOEBACHL 22-AUG-1997 14:49:24.76 @MASTER LOEBACHL BOI--VCL trapped in the bell of a regulator Summary: Jim Whiteaker, an instrumental and electrical technician, was releasing the spring pressure off a regulator when VCL vapors started blowing out the adjusting screw tap. In Attendance: --I & E Technician Ken Prather--BPS Tech. Phil Bregar--Tank Farm Operations Ron Kaminski--Resin Reclaim Tech. Larry Loebach--Line 1 Tech. Ron Moore--Production Manager Scott Johnson--S & E Engineer Rod Martin--S & E operations Pete Jacob--Plant Engineer Narrative: The VCL and recovery lines to the tank farm were recovered Saturday, Aug. 16, to replace threaded fittings of 1 inch or above with welded fittings. The VCL back-pressure regulator was removed from the circulation loop on Tuesday, Aug. 19 because it had 1 inch threaded taps. It was taken to the maintenance shop that day and it was communicated to I & E that the regulator came from redded NGC 13614 the VCL line. disconnected the piping to the regulator and started to release the spring pressure before taking the bolts off the bell assembly through the adjusting screw tap. put on a face shield and gloves and removed the regulator from the shop. He noticed that the adjusting screw had frost covering it. notified Pete Jacob and Steve Smith and repaired the regulator after the frost dissipated. Facts: a. The VCL & Recovery lines had been pulled down on vacuum through recovery and an equipment opening was written with a 500 ppm reading. b. The VCL & Recovery lines had been opened three days. c. The lines to and from the regulator had no vapors present. d. The regulator diaphragm was split leading one to believe no VCL vaoors could be trapped in the regulator. e. has 11 years experience as an X & E man. f. The intent was to weld 3/4 inch bushings into both of the 1" taps^ and reuse the regulator. g. The reason took the regulator apart was to protect the internal parts from the hot work. h. A 1/2 inch plug was found in the vent hole. i. Both diaphragms had hairline cracks. j. Numerous layers of paint on the regulator served as a seal around the adjusting screw threads. Management Systems: a. No procedures were violated. b. < will receive a blood test exposure to Vinyl Chloride. September 18, 1997 due to the potential Corrective Actions: a. Review the incident in all safety meetings. Raise the awareness of potential booby traps. Just because a line checks clear of a hazard, does not mean attached equiment is clear of the hazard. ( ___ Completed by Sept. 30, 1997 b. We removed the regulator from this service to determine if it is needed. This regulator was installed prior to the Rego relief valves. The Rego relief valves are a redundant system to the regulator. (Ongoing) Completed by September 15, 1997. c. Review safety procedure and modify as required to insure proper precautions are taken when dealing with equipment in hazardous service. (Loebach Johnson) September 15, 1997 Conclusion: The regulator diaphragms were cracked allowing liquid VCL to enter the bell assembly. The VCL pressure built up with the 1/2 inch plug in the vent hole. The regulator had been painted several times allowing the adjusting screw to seal. When the VCL and Recovery lines were recovered down the VCL in the bell was trapped and could not escape until loosened the adjusting screw. NGC 13615