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
• Prior to the incident, the Phillips union
maintenance group and management were
embroiled in numerous labor disputes
regarding the use of non-union sub-
• 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
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
• 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
• Excessive overtime - workers stressed-out.
• Use of sub-contract maintenance creates
• 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.
• 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
• 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
• 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
• Risk Management Plan (RMP) regulations for
Chemical / Petrochemical / Oil Industry were
adopted as Federal Regulation 1910.119 on 24
• All companies that exceed flammable and toxic
threshold quantities must apply to the EPA for
permits to operate.
• Emergency plans with the community are
Free Copy of RMP Program
• 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