Inspection Detail

Inspection: 306618505 - Atk Thiokol Corp

Inspection Information - Office: Utah Division Of Occupational Safety And Health

Investigation Summary

At approximately 10:46 p.m. on February 14, 2005, Employee #1 and Employee #2 were in the process of manually transferring material from a filter receiver into a 5-gallon bucket. The filter receiver, made of stainless steel, was 4 ft by 4 ft by 2 ft on the outside. The filter receiver was equipped with 4 caster wheels, approximately 4-in., located 8-in. off at each corner. The filter receiver had a 6-in. false bottom giving an effective 18-in. inside depth. A metal grid frame 1 ft by 1 ft was attached 6 in. from the bottom and was used to support a filter tray. A polypropylene, 25-micron filter blanket covered the bottom and sides of the filter receiver with some overhang. The filter receiver was equipped with a fitting on the bottom to facilitate either vacuum or supplied air through the false bottom of the filter receiver. Employee #1 and Employee #2 had brought in extra tools to facilitate the transfer when the material became hard to remove from the filter tray. This equipment included a 52-ounce cast aluminum scoop and a large, 3-ft polypropylene shovel. These tools, specifically the aluminum scoop were not approved for use as part of the process. An unexpected material in the bottom of the filter receiver exploded. It's assumed that the use of the aluminum scoop most likely caused the initiation of the explosion due to impact force. Employee #1 was killed. Employee #2 received substantial burn injuries to over 70 percent of her body and was hospitalized.

Keywords: BURN, HEAT, WORK RULES, EXPLOSION, EQUIPMENT APPROVAL