Detail of EJ/T 1217-2007

Introduction of EJ/T 1217-2007

1 Scope This standard specifies the framework for fully implementing fire hazard analysis for nuclear power plants and provides a detailed description for determining the fire safety adequacy of nuclear power plants, including data collection, analysis of fire growth, fire effect analysis, evaluation of the adequacy of fire safety measures, considerations before making improvements in fire safety, iterative analysis, etc. This standard is applicable to fire hazard analysis for land-based stationary thermal-neutron reactor nuclear power plants (including light water reactor, heavy water reactor and gas cooled reactor nuclear power plants). It is also applicable to fire hazard analysis for research reactor and other nuclear facilities. This standard is applicable to both new and existing nuclear power plants. It is applicable to all areas of the nuclear power plant, including non-nuclear facilities. It is not applicable to the fire hazard analysis of fire compartment of liquid metal facilities in liquid metal cooled reactor nuclear power plants. 2 Normative references The following normative documents contain provisions which, through reference in this standard, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply to this standard. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the referenced document applies. HAF 102 Safety specifications for design of nuclear power plant HAF 003 Safety specifications for quality assurance of nuclear power plant HAD 102/11 Fire protection for nuclear power plant HAD 103/10 Fire protection for operation of nuclear power plant 3 Terms and definitions For the purposes of this standard, the following terms and definitions apply: 3.1 combustion exothermic reaction of a substance with oxygen, generally accompanied by flames, glowing and (or) emission of smoke, or a combination thereof [HAD102/11, Glossary] 3.2 explosion abrupt oxidation or decomposition reaction producing an increase in temperature or in pressure, or in both, simultaneously 3.3 fire process of combustion characterized by the emission of heat accompanied by smoke or flame, or both 3.4 fire disaster caused by uncontrolled combustion in time and space 3.5 fire barrier walls, floor, ceiling or devices for closing passages such as doors, hatches, penetrations and ventilation systems that are used to limit the consequences of a fire. A fire barrier is characterized by a fire resistance rating [HAD102/11, Glossary] 3.6 fire compartment building or part of a building comprising one or more rooms or spaces, constructed to prevent the spread of fire to or from the remainder of the building for a given period of time. A fire compartment is completely surrounded by a fire barrier 3.7 fire cell subdivision of a fire compartment in which fire separation between items important to safety is provided by fire protection features (such as limitation of combustible materials, spatial separation, fixed fire extinguishing systems, fireproof coatings or other features) so that consequential damage to the other separated systems is not expected [HAD102/11, Glossary] 3.8 fire damper device that is designed, by automatic operation, to prevent the passage of fire through a duct, under given conditions [HAD102/11, Glossary] 3.9 fire load sum of the calorific energies that could be released by the complete combustion of all the combustible materials in a space, including the facings of the walls, partitions, floors and ceilings 3.10 fire resistance ability of an element of building construction, component or structure to fulfil, for a stated period of time, the required load bearing function, integrity and/or thermal insulation, and/or other expected duty specified in a standard combustion test [HAD102/11, Glossary] 3.11 fire retardant quality of a substance for suppressing, reducing or delaying markedly the combustion of certain materials 3.12 fire stop physical barrier designed to restrict the spread of fire in cavities within and between building construction elements 3.13 fire watch one or more individuals who are responsible for providing additional (e.g. during hot work) or compensatory (e.g. in case of system damage) services to a nuclear power plant activity or area in order to detect a fire or to identify activities and conditions that have potential fire risk. They shall be trained in identifying conditions and activities that have potential fire risk, as well as in the use of firefighting equipment and appropriate fire notification procedures [HAD103/10, Glossary] 3.14 non-combustible material material that, in the form in which it is used and under the conditions anticipated, will not ignite, support combustion, and bum or release flammable vapor when subject to fire or heat 3.15 secondary effect all subsequent effects caused by the consequence of the primary effect of the fire 3.16 fire containment approach arrangement that can prevent the fire from spreading from one fire compartment to another by maintaining the integrity of the fire barrier around each fire compartment within the specified fire time limit, thus achieving the basic conditions for isolating items important to safety [HAD102/11] 3.17 fire influence approach arrangements in certain fire zones, in order to limit the impact of fires on items important to safety, also necessary to prevent the spread of fire within the fire compartment. Including active fire detection, extinguishing or passive means, as well as appropriate space separation measures between components, are used to prevent fire from spreading from one fire compartment to another [HAD102/11] 4 Fire hazard analysis 4.1 General It is essential that the fire protection measures are adequate to ensure safety throughout the life of the nuclear power plant. This is achieved by defence in depth, the concept of which is described in HAD 102/11. This concept incorporates three principal objectives: a) to prevent fires from starting; b) to detect and extinguish quickly those fires that do start, thus limiting the damage; c) to prevent the spread of those fires that have not been extinguished, thus minimizing their effect on items important to safety. The key to fire hazard analysis is to determine the necessary fire resistance of fire barriers and the ability of fire related systems (detection systems, fire extinguishing systems, ventilation and smoke exhaust systems). 4.2 Purposes of fire hazard analysis The fire hazard analysis has the following purposes: a) to identify items important to safety and determine the position of their individual components in each fire compartment; b) to analyse the anticipated fire growth and the consequences of the fire with respect to items important to safety. The assumptions and limitations of the analytical method shall be clear; c) to determine the required fire resistance of fire barriers, especially to determine the required fire resistance of fire compartment (fire containment approach) boundary during the fire hazard analysis; d) to determine the necessary active and passive fire protection measures to achieve a safe state of fire; e) to identify cases where additional fire separation or fire protection is required, especially for common mode failures, in order to ensure that the safety system will remain functional during and following a credible fire. Fire hazard analysis shall be used to determine necessary active and passive fire protection measures of fire cell (fire influence approach). For existing plants, the purpose of fire hazard analysis is to document that the existing fire protection measures are adequate to ensure safety. In situations where deficiencies are identified during the analysis, the process requires recommendations to be formulated which, when implemented, will ensure that safety is achieved. 4.3 Personnel qualifications It is essential that the fire hazard analysis be prepared by technically qualified engineering personnel. This applies to preparation of the initial document and to periodic updating of the analysis. The experts needed to conduct the fire hazard analysis combines knowledge of fire engineering, and design and operation of nuclear power plant. The personnel that perform the analysis shall be familiar with the fire safety systems, components and equipment, and their interaction with safety systems. The analyst shall be capable of evaluating the fire damage effects on those structures, systems and components that are important to safety. These experts shall have capability of evaluating fire induced failures of the power circuit system, control and instrumentation system. Good familiarization with the design of the plant safety systems, and with plant layout, is essential. It is advisable that analysts have experience with application of the methods available for quantifying and analysing fire growth and of the computational methods for predicting the consequences of fires. To ensure that personnel have appropriate qualifications in all the necessary subjects, it is likely that a team composed of multi-professionals will be needed in preparing and updating the fire hazard analysis documentation. 4.4 Initial development and updating The fire hazard analysis documentation is usually developed early in the design of new nuclear power plants, updated before initial loading of the reactor fuel, updated periodically[1) The appropriate period for this review and update is generally 5-10 years, in addition to updates following significant nuclear power plant modifications.]1) and, when relevant, operational or plant modifications are proposed within the scope of the fire hazard analysis for nuclear power plants. For existing plants, it is important to perform a comprehensive fire hazard analysis at the earliest opportunity. Periodic updating of the fire hazard analysis documentation is done throughout the lifetime of the nuclear power plant (including some of the decommissioning phases). Retention of the documentation compiled for previous fire hazard analyses is very important. Relevant operational or nuclear power plant modifications that affect fire safety within the scope of the fire hazard analysis include physical changes in the nuclear power plant arrangement; increases in the fire load; modifications to or relocation of the systems, components or equipment; modifications to the fire detection or fire extinguishing systems or equipment; modifications to the passive fire protection measures; and changes in the ventilation system. 4.5 Quality assurance programme It is important that the existing nuclear power plant quality assurance programme be implemented for controlling fire safety. Detailed guidance on the quality assurance programme in nuclear power plants is provided in HAF 003 and related safety guides. This quality assurance programme is also applied to the preparation (including all the necessary iterations) and control of the fire hazard analysis report. In addition, all subsequent revisions and updates to the fire hazard analysis report are controlled and recorded to the same level of engineering review and approval that applied to the original document, in accordance with the applicable provisions of the quality assurance programme. This element of control is essential in order to provide reliable documentation that reflects current conditions in each fire compartment and fire cell throughout the plant, and to ensure that the analysis is maintained as a ‘living document’ throughout the life of the plant.

Contents of EJ/T 1217-2007

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Fire hazard analysis 5 Methods to be followed in preparing the fire hazard analysis 6 Data collection 7 Analysis of fire growth 8 Fire effect analysis 9 Evaluation of the adequacy of fire safety measures 10 Considerations before making improvements in fire safety 11 Iteration of analysis Annex A (Informative) Data collection Annex B (Informative) Example of fire preplan Annex C (Informative) Effect of ventilation system Annex D (Informative) Direct, indirect and secondary effects of fire and fixed fire extinguishing system Annex E (Informative) Other fire effects