| Case Name |
Explosion of 5- chloro -1,2,3- thiadiazole (5CT) |
| Pictograph |
|
| Date |
May 14, 1980 |
| Place |
Urawa, Saitama, Japan |
| Location |
Pharmaceutical factory |
| Overview |
An explosion occurred at a company during manufacturing a new material 5- chloro -1,2,3- thiadiazole (5CT) at a request. The cause of the accident might be that the both a manufacturing consigner and a manufacturing contractor had little knowledge of the potential hazard of 5CT. |
| Incident |
In trial manufacture of 5CT, an explosion and fire occurred during packaging work into a transfer container after vacuum distillation. Harmful gas was generated, and adjacent residents were evacuated. |
| Processing |
Manufacture |
| Individual Process |
Filling and subdivision |
| Substance |
5- chloro -1,2,3- thiadiazole(5CT), Fig3 |
| Type of Accident |
Explosion, fire |
| Sequence |
5CT was distilled under reduced pressure at 50 mmHg. The first fraction was discarded in the morning and the main fraction was collected in a 500 L receiver drum in the afternoon. Afterwards, the receiver drum was heated (the freezing point of 5CT is 20-25 °C) again after water-cooling to about 40 °C with steam. The explosion occurred during packaging work while a chemical hose was connected to a flash valve and 5CT was filled to chemical drum. |
| Cause |
not clear |
| Countermeasures |
Countermeasures were not taken because of the cause is unknown. |
| Knowledge Comment |
For a newly handled material, an assessment of potential hazards is necessary. |
| Background |
The potential hazard of 5CT |
| Sequel |
5CT easily ignites in a container due to friction or impact. It easily explodes when ignites, and reacts intensely to heat. The explosive power is about 80% that of TNT. The facts above were proven in the investigation after the accident. |
| Incidental Discussion |
In those days, 5CT was a newly handled material in Japan. However, there were records of an explosion at BASF Co. in Germany. Besides, there is an article in a magazine that says the major company that requested the manufacture of 5CT to this company might have known the explosion hazard of 5CT, because another explosion had occurred at a different 5CT manufacturing company, which was a contractor of the major company a year before, and moral responsibility of the major company became an issue. |
| Reason for Adding to DB |
Example of explosion of material with unknown hazards |
| Scenario |
| Primary Scenario
|
Organizational Problems, Inflexible Management Structure, Acceptance of Unfair Requirement, Insufficient Analysis or Research, Insufficient Prior Research, No Evaluation about Potential Hazard, Non-Regular Action, Change, Execution of New Experiment, Secondary Damage, External Damage, Explosion, Bodily Harm, Death, 2 pereson died, Bodily Harm, Injury, 12 person injured, Damage to Society, Social Systems Failure, 600 person emergency refuge, 400 houses damaged, Loss to Organization, Economic Loss
|
|
| Sources |
Fire and Disaster Management Agency, Examples of accidents manufacturers of dangerous objects, 1981, pp.222-223
Fire-Defense Headquarters of the Urawa City. K chemical and synthetic industry fire caused by explosion - outline, Modern fire fighting, No.212, pp.113-116(1980)
Masamitsu Tamura, Mitsuru Arai, Yoshiaki Akutsu, 5CT explosion, High - energy material and safety, pp.58-59(1999).
|
| Number of Deaths |
2 |
| Number of Injuries |
17 |
| Physical Damage |
36 buildings of factories, etc. collapsed or partially collapsed. 397 adjacent residential units and windows were damaged. |
| Consequences |
Hydrogen chloride gas was generated with an offensive odor in the vicinity and things fell down from shelves in adjacent residential units. 19:13, on May 14th, 1980: An evacuation order was announced to adjacent residents because of the hazard of explosion and/or pollution by harmful gas, and about 610 persons were evacuated to three locations, The order was canceled at 08:00, on May 15th, |
| Multimedia Files |
Fig2.Chemical formula
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| Field |
Chemicals and Plants
|
| Author |
ARAI, Mitsuru (Environmental Science Center, The University of Tokyo)
TAMURA, Masamitsu (Center for Risk Management and Safety Sciences, Yokohama National University)
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