This is a chronological list of orphan source incidents and accidents.
Note: As incident reporting has used inconsistent units of measurement, here are the conversion factors; metric prefixes are used where appropriate: kilo (k), mega (M), giga (G), tera (T):
Property | non-SI unit | SI unit equivalent |
---|---|---|
Radioactivity | 1 Curie (Ci) | 37 gigabecquerels (GBq) |
Equivalent radiation dose | 1 rem | 0.01 Sievert (Sv) |
Absorbed radiation dose | 1 rad | 0.01 Gray (Gy) |
A dirty bomb or radiological dispersal device is a radiological weapon that combines radioactive material with conventional explosives. The purpose of the weapon is to contaminate the area around the dispersal agent/conventional explosion with radioactive material, serving primarily as an area denial device against civilians. It is not to be confused with a nuclear explosion, such as a fission bomb, which produces blast effects far in excess of what is achievable by the use of conventional explosives. Unlike the rain of radioactive material from a typical fission bomb, a dirty bomb's radiation can be dispersed only within a few hundred meters or a few miles of the explosion.
Acute radiation syndrome (ARS), also known as radiation sickness or radiation poisoning, is a collection of health effects that are caused by being exposed to high amounts of ionizing radiation in a short period of time. Symptoms can start within an hour of exposure, and can last for several months. Early symptoms are usually nausea, vomiting and loss of appetite. In the following hours or weeks, initial symptoms may appear to improve, before the development of additional symptoms, after which either recovery or death follow.
The becquerel is the unit of radioactivity in the International System of Units (SI). One becquerel is defined as an activity of one per second, on average, for aperiodic activity events referred to a radionuclide. For applications relating to human health this is a small quantity, and SI multiples of the unit are commonly used.
A nuclear and radiation accident is defined by the International Atomic Energy Agency (IAEA) as "an event that has led to significant consequences to people, the environment or the facility." Examples include lethal effects to individuals, large radioactivity release to the environment, or a reactor core melt. The prime example of a "major nuclear accident" is one in which a reactor core is damaged and significant amounts of radioactive isotopes are released, such as in the Chernobyl disaster in 1986 and Fukushima nuclear disaster in 2011.
The Goiânia accident was a radioactive contamination accident that occurred on September 13, 1987, in Goiânia, Goiás, Brazil, after an unsecured radiotherapy source was stolen from an abandoned hospital site in the city. It was subsequently handled by many people, resulting in four deaths. About 112,000 people were examined for radioactive contamination and 249 of them were found to have been contaminated.
Cobalt-60 (60Co) is a synthetic radioactive isotope of cobalt with a half-life of 5.2714 years. It is produced artificially in nuclear reactors. Deliberate industrial production depends on neutron activation of bulk samples of the monoisotopic and mononuclidic cobalt isotope 59
Co
. Measurable quantities are also produced as a by-product of typical nuclear power plant operation and may be detected externally when leaks occur. In the latter case the incidentally produced 60
Co
is largely the result of multiple stages of neutron activation of iron isotopes in the reactor's steel structures via the creation of its 59
Co
precursor. The simplest case of the latter would result from the activation of 58
Fe
. 60
Co
undergoes beta decay to the stable isotope nickel-60. The activated cobalt nucleus emits two gamma rays with energies of 1.17 and 1.33 MeV, hence the overall equation of the nuclear reaction is: 59
27Co
+ n → 60
27Co
→ 60
28Ni
+ e− + 2 γ
Caesium-137, cesium-137 (US), or radiocaesium, is a radioactive isotope of caesium that is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons. Trace quantities also originate from spontaneous fission of uranium-238. It is among the most problematic of the short-to-medium-lifetime fission products. Caesium-137 has a relatively low boiling point of 671 °C (1,240 °F) and easily becomes volatile when released suddenly at high temperature, as in the case of the Chernobyl nuclear accident and with atomic explosions, and can travel very long distances in the air. After being deposited onto the soil as radioactive fallout, it moves and spreads easily in the environment because of the high water solubility of caesium's most common chemical compounds, which are salts. Caesium-137 was discovered by Glenn T. Seaborg and Margaret Melhase.
Radioactive scrap metal is created when radioactive material enters the metal recycling process and contaminates scrap metal.
This is a list of criminal acts intentionally involving radioactive substances. Inclusion in this list does not necessarily imply that anyone involved was guilty of a crime. For accidents or crimes that involved radioactive substances unbeknownst to those involved, see the Nuclear and radiation accidents and incidents.
This article compares the radioactivity release and decay from the Chernobyl disaster with various other events which involved a release of uncontrolled radioactivity.
K-431 was a Soviet nuclear-powered submarine that had a reactor accident on 10 August 1985. It was commissioned on 30 September 1965. The 1985 explosion occurred during refueling of the submarine at Chazhma Bay, Dunay, Vladivostok. There were ten fatalities and 49 other people suffered radiation injuries. Time magazine has identified the accident as one of the world's "worst nuclear disasters".
The 1990 Clinic of Zaragoza radiotherapy accident was a radiological accident that occurred from 10 to 20 December 1990, at University Clinic Hospital Lozano Blesa of Zaragoza, in Aragon, Spain.
The RaLa Experiment, or RaLa, was a series of tests during and after the Manhattan Project designed to study the behavior of converging shock waves to achieve the spherical implosion necessary for compression of the plutonium pit of the nuclear weapon. The experiment used significant amounts of a short-lived radioisotope lanthanum-140, a potent source of gamma radiation; the RaLa is a contraction of Radioactive Lanthanum. The method was proposed by Robert Serber and developed by a team led by the Italian experimental physicist Bruno Rossi.
From 1946 through 1993, thirteen countries used ocean disposal or ocean dumping as a method to dispose of nuclear/radioactive waste with an approximation of 200,000 tons sourcing mainly from the medical, research and nuclear industry.
A radiation accident occurred in Samut Prakan Province, Thailand in January–February 2000. The accident happened when an insecurely stored unlicensed cobalt-60 radiation source was recovered by scrap metal collectors who, together with a scrapyard worker, subsequently dismantled the container, unknowingly exposing themselves and others nearby to ionizing radiation. Over the following weeks, those exposed developed symptoms of radiation sickness and eventually sought medical attention. The Office of Atomic Energy for Peace (OAEP), Thailand's nuclear regulatory agency, was notified when doctors came to suspect radiation injury, some 17 days after the initial exposure. The OAEP sent an emergency response team to locate and contain the radiation source, which was estimated to have an activity of 15.7 terabecquerels (420 Ci), and was eventually traced to its owner. Investigations found failure to ensure secure storage of the radiation source to be the root cause of the accident, which resulted in ten people being hospitalized for radiation injury, three of whom died, as well as the potentially significant exposure of 1,872 people.
A radioactive source is a known quantity of a radionuclide which emits ionizing radiation, typically one or more of the radiation types gamma rays, alpha particles, beta particles, and neutron radiation.
The Lia radiological accident began on December 2, 2001, with the discovery of two orphan radiation sources near the Enguri Dam in Tsalenjikha District in the country of Georgia. Three villagers from Lia were unknowingly exposed. All three men were injured, one of whom eventually died. The accident was a result of unlabeled radioisotope thermoelectric generator (RTG) cores which had been improperly dismantled and left behind from the Soviet era. The International Atomic Energy Agency (IAEA) led recovery operations and organized medical care.
The theft of radioactive material in Tammiku took place in 1994. Three brothers in Tammiku, Männiku, Saku Parish, Estonia, who were scrap metal scavengers, entered a fenced area in the woods and broke into a small shed that was seemingly abandoned, with stairs leading to an underground hall. The brothers did not know that the buildings were nuclear waste storage facilities. One of the brothers, Ivan, suffered a crush injury when a drum fell onto him. The brothers placed some pieces of metal into their pockets and went home, planning to return later. Ivan placed a metal cylinder in his pocket, not knowing that it was a strong caesium-137 radioactive source that was released from a container broken by the falling drum. He received a 4,000 rad whole-body dose and died 12 days later. Only after Ivan's family's dog died, and Ivan's stepson showed radiation burn of his hands, was the cause of Ivan's death identified. The delay in information was due to the brothers' reluctance to admitting to the break-in.
A radioactive contamination incident occurred in 1984 in Ciudad Juárez, Mexico, originating from a radiation therapy unit purchased by a private medical company and subsequently dismantled for lack of personnel to operate it. The radioactive material, cobalt-60, ended up in a junkyard, where it was sold to foundries that inadvertently melted it with other metals and produced about 6,000 tons of contaminated rebar. These were distributed in 17 Mexican states and several cities in the United States. It is estimated that 4,000 people were exposed to radiation as a result of this incident.