Case Ditails

Case Name Explosion in the workroom to fill explosives with press
Date April 16, 1996
Place Edajima, Hiroshima, Japan
Location Explosives factory
Overview An explosion accident occurred in the press workroom of an explosives manufacturing factory. Three employees who were in the work room were killed. When PBX press work for manufacturing blasting fuses or exposal preparation work of waste explosives and defective goods were being conducted, explosives kept there exploded. The progress of the accident was presumed as following: Sensitive explosives ignited and exploded during preparatory work for disposing of waste explosives and defective goods because of slight impact or static electricity. In addition, the explosion expanded to explosives stored in the vicinity, and a large explosion occurred.
PBX: A kind of explosive, abbreviation of Plastic Bonding Explosive.
Incident Explosives being kept in a press workroom exploded, and three workers in the workroom died. Refer to Fig2.
Processing Manufacture
Individual Process Other
Substance Explosive
High explosive
Type of Accident Explosion
Sequence 1. What kind of work being carried out in the press workroom was not known, because all of the workers in the workroom were killed. It was presumed that manufacturing of blasting fuses by PBX pressing or preparatory work for disposal of waste explosives and defective goods were being carried out.
2. Workers left the office of the explosives section on April 16th at 08:15 and arrived at the press workroom at 08:20. Then work started. The explosion occurred at 08:35.
3. In the testimony of a nearby employee, there were three explosions, and white smoke and flames were seen when the first explosion sound was heard. The flames grew after the second explosion, and flames rose to about one and a half times as high as the workroom at the third explosion.
Cause 1. The cause of the accident was difficult to specify because all of the workers in the press workroom were killed, and the workroom was completely destroyed. A scenario to the large explosion was presumed as follows: Sensitive explosives ignited and exploded due to small impacts or static electricity during preparatory work for disposing of retained waste explosives and defective goods. Then, explosives kept in the vicinity exploded one after another, and a large explosion occurred
2. Damage expanded because a large amount of gunpowder such as waste explosives and defective goods were kept in the workroom. They were not necessary for work on that day.
Countermeasures 1. Strengthening safety countermeasures for explosives that are highly sensitive to impact and static electricity.
2. Improving the manufacturing safety manual.
3. Strengthening safety management such as inspection of the operating manual by the explosives manufacturing protection manager and safety inspection of the field-work.
4. Strengthening safety education.
Knowledge Comment Explosives kept in workrooms are limited to the necessary minimum for the work, in particular, when sensitive explosives are manufactured or are handled. Otherwise, protection measures are taken.
Background 1. The explosives management system of the office had become stereotyped.
2. Usually the manager in the office did not sufficiently grasp the field-work.
Reason for Adding to DB Example of accident due to an insufficient check on the work by an executive safety staff
Primary Scenario Organizational Problems, Poor Management, Slackness of Management, Poor Value Perception, Poor Safety Awareness, Inadequate Risk Recognition, Usage, Transport/Storage, Storage, Malicious Act, Rule Violation, Act Violation, Secondary Damage, External Damage, Explosion, Bodily Harm, Death, 3 person died, Loss to Organization, Economic Loss, 15 buildings damaged
Sources Outline of significant accidents in 1996, Safety yearbook, p.244
The explosive pressure workroom of C powder Co., Ltd. E factory accident investigation committee. Research report on accident in the fourth explosive press workroom f C powder Co., Ltd. E factory.(1997)
Number of Deaths 3
Physical Damage Complete collapse of a workroom. The roofs and the windows of 15 other workrooms were damaged. Destruction of an oil hydraulic press, a movable air press, a movable Numarocc press, an automatic explosives press, and worktables. About 2.8 kg of low explosives and about 1.9 kg of high explosives were dispersed.
Multimedia Files Fig2.Photograph of damaged situation
Field Chemicals and Plants
Author OGAWA, Terushige (Graduate School of Environment and Information Sciences, Yokohama National University)
TAMURA, Masamitsu (Center for Risk Management and Safety Sciences, Yokohama National University)