Samut Prakan radiation accident
The nuclear accident in Samut Prakan happened in February 2000 in Thailand. Through the release of ionizing radiation from a defunct medical cobalt -60 irradiator while at least three people were killed and more than a thousand were exposed to increased radiation exposure. Presumably this case, the area of a junkyard in Samut Prakan ( 20 km in a straight line from the center of Bangkok ) was.
Accident and its discovery
Trigger of the event were several sources that originated from devices for radiation therapy and were stored since October 1999 by a company illegally on an unprotected parking in Bangkok. To the actual accident occurred when a scrap collectors of these sources brought into their possession, they spent a junkyard and there set off the protective coating in order to resell the materials (lead, steel) can separately.
The attached to the housing of the radiation source written warning - which was not written in Thai language - and the presence of the radiation warning sign on the shroud was neither the scrap collectors, even the junkyard workers or the junkyard owner paid attention, may have been the people who significance not known.
In the coming days, developed with all stakeholders, the typical symptoms of high radiation exposure: nausea, loss of appetite, diarrhea, sunburn- like skin damage, ultimately large-scale, open sores and hair loss. Despite these complaints, the scrap collectors were still only about a week after the break-up of the radiation source medical attention at a nearby hospital. The doctors working there interpreted the present clinical pictures again after a few days right as radiation sickness after the employees of the scrap yard also came to the hospital with similar symptoms. A total of ten people associated with the scrap collectors were exposed to the radiation particularly strong through the open cobalt - 60 source.
Meanwhile had passed since the exposure of the source 17 days and this has often been overwhelmed in the little parent material heap of junkyard scrap. After the competent authority has been set on the assumption that the living environment of the patient would have to find an unprotected source, informed immediately began the search for the source and the preparation for salvage.
Salvage
Measurements performed at the junkyard were very high radiation levels: At the entrance of the junkyard, about seven feet away from the source of value was 50 mSv / h Directly at the scrap heap with the open source yielded the measurements up to 10 Sv / h (For comparison: . Liquidators that were used in the Chernobyl disaster on the reactor roof for cleanup, direct got there within about a minute, a dose of about 200 mSv, which corresponds to 12 Sv / h at the open source at the junkyard was thus the radiation - however limited to a relatively small area -. at a comparable level as in Chernobyl )
An evacuation was initially drawn by the competent authorities considered, but then rejected, as not to cause panic. Only a barrier for the dose range above 0.3 mSv / h was performed, corresponding to a radius of about ten meters around the junkyard.
A quick recovery and backup of the cobalt - 60 source was complicated by the fact that on one hand the exact location of the source was not known and further the work has been carried large amounts of other scrap camped unsorted on the site, disabled. In addition, the active forces were equipped regarding rescue equipment and protective gear poorly. Therefore unconventional means have been applied: So was to localize the radiation source in the junkyard a fluorescent plate used, which was mounted on the tip of a long bamboo rod. While working at night was so successful the position of the source can be determined because the plate was placed near the source, this glow. For this purpose, however, had to wait until no disturbing moonlight was no longer present. The source was finally separated from the rest of scrap and stored in a lead container.
The salvage work a total of 52 persons were employed. The highest resulting radiation exposure to persons from this group was 32 mSv.
Consequences and effects of the accident
The people living in the vicinity of the scrap yard were exposed over a period of about three weeks of radiation exposure that exceeded the naturally occurring radiation in the environment many times. Within a radius of 100 meters around the junkyard lived at the time of the accident in 1872 people. A group of 258 people living in the vicinity of 50 meters around the junkyard, including five pregnant women. One of these women chose because of the accident for an abortion.
The radiation exposure during the ten directly involved (scrap collector and dealer, junkyard - workers and relatives of such persons ) was enormous subsequent calculations showed for four whole-body doses of about 2 Gy, for two other individuals had values between 2 Gy and 6 Gy and the remaining four strains suffered by more than 6 Gy. The equivalent dose for the different persons cohorts was thus - because it was a gamma-ray exposure - in each case about 2 Sv, 2 Sv to 6 Sv and more than 6 Sv. Of the latter, four participants died two 18 and 20 year-old male employee of the junkyard proprietor, and her husband, within eight weeks.
After several years of litigation sentenced in 2009 a Thai court, responsible for the illegal storage of radiation sources Company ( Kamol Sukosol Electric Co Ltd ) to pay compensation amounting to a total of 640 276 baht. Divided into the twelve applicants in this process, radiation victims this results in a total compensation of each translated to around 1,300 euros.
Consequences at the international level
This and similarly stored accidents led by the IAEA for the development of the new additional warning symbol for dangerous radioactive material that has been specially designed so that even uneducated groups of people (for example children, illiterate ) be able to interpret the symbols correctly.