Industrial and Medical Nuclear Accidents. Jean-Claude Amiard

New Delhi India Discovery of radioactive materials in scrap metal stores and irradiation of a scrap metal dealer 2011 Use of radiography Bulgaria Irradiation by a cobalt 60 source of four workers involved in an ionizing radiation sterilization facility Level 3 1981 The Hague France Fire in a storage silo 1991 Smolensk Russia Exceeding the operating boundary conditions during restart tests following a maintenance shutdown of reactor 2 at the nuclear power plant 1992 Sellafield UK Nitrated plutonium leak in a containment cell at the Sellafield fuel reprocessing facility 1993 Narora India Loss of power supply to reactor 1 at the nuclear power plant 1993 Kola Russia Emergency shutdown of reactor 1 at the nuclear power plant 2002 Roissy France Incident during the transport of a package by Federal Express between Sweden and the United States via Roissy airport 2002 Davis–Besse USA Discovery of a cavity in the vessel cover on the power plant reactor due to boric acid corrosion of the metal 2002 New Orleans United States High dose rate measured on a package from Sweden containing iridium 192 sources 2003 Paks Hungary Release of radioactive gases from cracked fuel rods stored in a cleaning tank located next to the fuel pool at the plant 2004 Puerto Rico Puerto Rico Irradiation by a cobalt 60 source of two workers involved in an ionizing radiation sterilization facility 2005 Sellafield UK Detection of a radioactive leak on a pipe in the THORP fuel reprocessing facility 2008 Toulouse France Irradiation by a cobalt 60 source of a worker working in an irradiation bunker on the ONERA site 2008 Fleurus Belgium Abnormal release of iodine 131 from the chimney of the Institut des radioélements building during a transfer of liquid effluent between tanks 2008 São Paulo Brazil Irradiation of an American and a Brazilian worker during the replacement of the cobalt 60 source of a cobalt therapy device in a state hospital

Level 7 is used by all for the Chernobyl accident [IAE 13] and Fukushima [IRS 17e], level 6 for Kyshtym and level 5 for Three Mile Island [IAE 13]. On the contrary, the ASN [ASN 16] classifies the 1957 Windscale accident as level 4 and the IAEA [IAE 13] as level 5. In its list, the ASN ignores the Goiânia accident in Brazil in 1987 [IAE 13] and the accident at the Chalk River nuclear laboratories in Canada in 1952 [MOR 15], classified at level 5.

      The ASN ignores the accident of October 17, 1969 in Saint Laurent with the fusion of 50 kg of uranium from the Saint-Laurent-A1 nuclear power plant in France during loading [IRS 15a]. Similarly, the ASN ignores the core fusion at the Lucens nuclear power plant in Switzerland on January 21, 1969 [CAN 11], classified at level 5 by the OFPP (Office fédéral de la protection de la population) [OFP 15]. The ASN [ASN 16] classifies the Fleurus accident (Institut national des radioélements) in Belgium in 2006 as level 3 and the IAEA [IAE 13] as level 4.

      The level 3 incidents reported by the various official sources widely differ. While the ASN retains the Sellafield accident in 2005 [IAE 13] and the silo fire in The Hague in 1981 [FRA 14], several incidents reported by the IAEA [IAE 13], such as the loss of a source causing severe burns in 1999 in Yanango (Peru) or the same year in Ikitelli (Turkey) [IAE 13], are ignored. Further examples are the exposure of a worker to a radioactive source at ONERA in Toulouse (March 18, 2008) and of three temporary employees who entered an industrial accelerator in operation and were heavily irradiated in Forbach (Moselle) in 1991 [IRS 17e]. This was also the case for a radioactive leak (¹⁹²Ir) from a drum shipped from Sweden to the United States, transiting through Roissy (December 2001–January 2002) [ANO 02].

      The most serious nuclear accidents involving reactors are those involving the melting of the fuel contained in their core. From an analysis of the various lists of nuclear accidents [SOV 08, ROG 11], we can consider that at least 12 reactors have been destroyed by this phenomenon since 1952. These are the Windscale plutonium cell (United Kingdom) in 1957 (but which we classified as a military accident), the Chalk River CANDU reactor (Canada) in 1958, the Simi Valley sodium-cooled experimental reactor (California) in 1959, the Monroe sodium-cooled demonstration breeder reactor (Michigan) in 1966, the Chapelcross reactor (United Kingdom) in 1967, the Lucens experimental reactor (Switzerland) in 1969, the pressurized water reactor at Three Mile Island (Pennsylvania) in 1979, the graphite-gas A2 reactor at Saint-Laurent-des-Eaux (France) in 1980, the Chernobyl reactor (Soviet Union) in 1986 and the three reactors at Fukushima (Japan) in 2011.

These are not the only reactors whose cores have suffered. For example, according to Wing and Hirsch [WIN 06], at least four of the reactors located at the Santa Susana Field Laboratory (SSFL) site have suffered such accidents. These are the AE6 reactor which suffered a release of gaseous fission products into the environment in March 1959, the SRE which had a power excursion and partial core meltdown in July 1959, the SNAP8ER which in 1964 suffered 80% damage to its nuclear fuel and the SNAP8DR which in 1969 suffered similar damage to one-third of its nuclear fuel. Let us also recall the accident in 1961 of the Idaho Falls SL-1 experimental reactor discussed in the previous volume [AMI 19], or that of the Jaslovske Bohunice reactor (Czechoslovakia) in 1977, but where the consequences were much more limited.

      For nuclear workers, the number of accidents with clinical consequences is limited and tends to decrease for criticality accidents. On the contrary, the number is greater and tends to increase for accidents with radionuclides and especially for accidents related to sealed sources (Figure 1.2).

      Figure 1.2. Trends in the various types of nuclear and radiological accidents with clinical consequences for nuclear workers (adapted from [UNS 00a]). For a color version of the figure, see www.iste.co.uk/amiard/industrial.zip

1.6.