This paper focuses on the strategy that could be used to resolve this issue with the complement and the exploitation of the experimental validation. | How to obtain an enhanced extended uncertainty associated with decay heat calculations of industrial PWRs using the package EPJ Nuclear Sci. Technol. 5 8 2019 Nuclear Sciences J. Huyghe et al. published by EDP Sciences 2019 amp Technologies https epjn 2019002 Available online at https REGULAR ARTICLE How to obtain an enhanced extended uncertainty associated with decay heat calculations of industrial PWRs using the package Jordan Huyghe1 Vanessa Vallet1 David Lecarpentier2 Christelle Reynard-Carette3 and Claire Vaglio-Gaudard1 1 CEA DEN DER Cadarache 13108 Saint Paul-lez-Durance France 2 EDF Research and Development 7 Boulevard Gaspard Monge 91120 Palaiseau France 3 Aix Marseille Univ. Université de Toulon CNRS IM2NP Marseille France Received 27 June 2018 Received in final form 20 December 2018 Accepted 27 March 2019 Abstract. Decay heat is a crucial issue for in-core safety after reactor shutdown and the back-end cycle. An accurate computation of its value has been carried out at the CEA within the framework of the package. The package benefits from a Verification Validation and Uncertainty Quantification VVUQ process. The VVUQ ensures that the parameters of interest computed with the package have been validated over measurements and that biases and uncertainties have been quantified for a particular domain. For the parameter decay heat there are few integral experiments available to ensure the experimental validation over the whole range of parameters needed to cover the French reactor infrastructure fissile content burnup fuel cooling time . The experimental validation currently covers PWR UOX fuels for cooling times only between 45 minutes and 42 days and between 13 and 23 years. Therefore the uncertainty quantification step is of paramount importance in order to increase the reliability and accuracy of decay heat calculations. This paper focuses on the strategy that could be used to .