Inspection Detail

Inspection: 114616147 - Inberg-Miller Engineers Dba Inberg Surveying Co

Inspection Information - Office: Wyoming Department Of Workforce Services - Osha Division

Investigation Summary

DUE TO THE FACT THAT THE ALKYLATION UNIT WENT DOWN TWO DAYS EARLIER, AND NO STORAGE CAPACITY WAS LEFT (BULLET TANKS AND RAILROAD CAR BOTH WERE FULL), EMPLOYEES #1 THROUGH #6 WERE SENDING THE OLEFINS TO THE BLOWDOWN TANK. WHEN THE BLOWDOWN TANK BEGAN TO FILL UP, THE LIQUID MOVER SENT THE OLEFINS TO A NON-PRESSURIZED SLOP TANK. VAPORS WERE BEING RELEASED DUE TO THE VAPOR PRESSURE OF THE OLEFINS (C2-C3-C4). ADDITIONAL HEAT WAS ADDED TO THE TANKS WHEN A DECISION WAS MADE TO ADD HEAVY OILS TO THE SLOP TANK TO CONTROL THE TIGHT ENDS, THUS INCREASING THE VAPORS, AS THE HEAVY OILS WERE CLOSE TO 200 DEGREES FAHRENHEIT. THE INCREASING PRESSURE INSIDE AN ATMOSPHERE TANK CAUSED THE MASSIVE VOLUME OF VAPORS TO BE RELEASED. THE OLEFINS WERE IGNITED BY AN UNKNOWN CAUSE. THE EXPLOSION CAUSED DAMAGE 300 YARDS TO THE SOUTHWEST AND 150 YARDS TO THE NORTH. THIS EXTENSIVE AREA WAS DUE TO WIND DIRECTION, WIND SPEED, AND BUILD-UP OF VAPORS. EMPLOYEE #1 DIED AND EMPLOYEES #2 THROUGH #6 WERE SERIOUSLY BURNED.

Keywords: FLAMMABLE VAPORS, EXPLOSION, TANK, INATTENTION, BURN, VAPOR