The Phillips 66 Company Houston Chemical Complex Explosion and Fire, 23 Oct 89 23 killed, 130 Injured, $1,300MM damage Presented to ES-317y at UWO in 1999 Dick Hawrelak

The Process

Settling Legs

The Incident Prior to the incident, the Phillips union maintenance group and management were embroiled in numerous labor disputes regarding the use of non-union sub-contractors. On Sunday Oct 22, a sub-contractor crew began work to unplug 3 of 6 settling legs on Reactor No. 6.

The Incident Cont’d Near the end of the job on Monday Oct 23, a contractor went to the CR to seek the assistance of an operator when vapor was seen coming from the open pipe. 85,200 lbs of mostly isobutane were released from reactor No.6 in a few seconds.

The Incident Cont’d The first VCE took place two minutes after the release.The ignition source was unknown. A fire covered the reactor area. The second VCE took place 10 to 15 minutes later when two 90,920 liter isobutane storage tanks exploded. 25 to 45 minutes later a second reactor loop exploded.

The Consequences 23 workers on site were killed. More than 130 workers on site were injured. The unhardened control room disappeared. Missiles were thrown 9.5 km. into the community. Luckily, no one was injured. Property damage now stands at $1,300MM. Lloyds of London nearly goes bankrupt.

Overpressure - 32 Tonnes TNT

Reasons Cited By The Union Manpower cut-backs raised concerns for safety. Excessive overtime - workers stressed-out. Use of sub-contract maintenance creates conflict. Inadequate lock-out procedures. Inherently flawed reactor design.

Reasons Cited By Management All of the union citations were refuted by management citing that the system in place had worked safely for 20 years.

OSHA Report After the explosion, a physical examination of the actuator mechanism for the DEMCO valve showed, and FBI laboratory tests confirmed, that the DEMCO valve was open at the time of the release. The tests showed that the air hoses that supplied the air pressure (by which the actuator mechanism opened or closed the valve) were improperly connected in a reversed position. The hoses, connected in that way, would open a closed DEMCO valve even when the actuator switch was in the closed position.

Findings By OSHA Settling leg not completely cleared. The sub-contractor had reconnected the air supply set on the Demco valve incorrectly. When activated, the valve would open instead of closing. Since there was no flow the operators felt the job had been completed properly.

Findings By OSHA Cont’d There was no flow because of the remaining plug. The plug clears under start-up pressure and the reactor contents are dumped to the process pad area.

Other OSHA Findings Process hazard studies had not been performed. Maintenance procedures were inadequate. Effective safety permit not enforced. No HC gas detectors in the area. CR not hardened & too close to process.

Other OSHA Findings Cont’d Ventilation in many buildings inadequate. Fire protection system not maintained for readiness.

Follow-up Risk Management Plan (RMP) regulations for Chemical / Petrochemical / Oil Industry were adopted as Federal Regulation 1910.119 on 24 May 96. All companies that exceed flammable and toxic threshold quantities must apply to the EPA for permits to operate. Emergency plans with the community are required.

Free Copy of RMP Program http://www.epa.gov/ceppo/tools/rmp-comp/comp-dwn.html U.S. EPA RMP program now being used in Sarnia by the Chemical valley. RMP End-points are: 1 psig for VCEs 2nd Degree Burns for flash fires. ERPG2 for Toxic Chemicals Distances are too far reaching to permit an effective emergency response plan (RAH opinion).