Ever since the first commercial nuclear power reactors were built, there has been concern about the possible effects of a severe nuclear accident, coupled with the question of who would be liable. This concern was based on the supposition that, even with reactor designs considered safe, a cooling failure causing the core to melt would result in major consequences akin to those of the Chernobyl disaster. Experience over five decades has shown this fear to be exaggerated, so that the impact of a severe accident or terrorist attack is very likely to be localized and small. Following the Chernobyl disaster in 1986, the IAEA initiated work on all aspects of nuclear liability in an effort to improve the basic conventions and establish a comprehensive liability regime. Before 1997, the international liability regime was embodied primarily in two instruments: the OECD’s Paris Convention on Third Party Liability in the Field of Nuclear Energy of 1960 (NEA, 1960), in force since 1968 (bolstered by the Brussels Supplementary Convention of 1963) and the IAEA’s Vienna Convention on Civil Liability for Nuclear Damage of 1963, in force since 1977 (IAEA, 1963).

More recently, liability has become a much more relevant factor in the context of global nuclear safety and security. Nuclear liability is now channelled exclusively to the operator of the nuclear installation and the liability of the operator is absolute, i. e. the operator is held liable irrespective of where the fault originates. The potential cross-boundary consequences of a nuclear accident require an international nuclear liability regime, so national laws are supplemented by a number of international conventions. Liability is limited by both international conventions and by national legislation, so that beyond the limit (normally covered by insurance for third-party liability) the state can accept responsibility as insurer of last resort, as in all other aspects of industrial society. It is the government’s role to ascertain that the commitment to the international liability regimes is kept by its nuclear operators. Liability is limited in time (generally ten years after an accident, but national law may provide modifications) and amount (roughly now to a limit of US$ 300 million[7]). The operator is obliged to maintain insurance for an amount corresponding to its liability.