Public plant safety

Guide for the Identification and Control of Exothermic Chemical Reactions" (TAA-GS-05 1994). A document in German by the Technischer Ausschuss fur Anlagensicherheit (Technical Committee for Plant Safety) of the Federal Ministry of the Environment, Nature Conservation and Reactor Safety. Addresses safety assessment of reactions during both normal operations and excursions, as well as selection and extent of measures to be adopted. An English translation of this document is provided on the CD-ROM included with this publication. 

Public opinion is more critical and controversial about aspects of our responsibility in terms of product and plant safety and, increasingly, social responsibility, in particular with regard to employees. However, only a maximum of 15 percent of the population categorically deny that the industry is aware of its responsibilities, though the figure goes up in times of high-profile problems. 

We should, therefore, not allow ourselves to be thrown off track by a few loud voices uttering general fears of chemical products and chemical production. Nevertheless, particularly on such subjects as product and plant safety, we must make planned and realized improvements dear to the public - and we do so in our very detailed annual Responsible Care Report - to further increase their understanding and acceptance of the realities of our industry. 

The problem and the required solution will dictate the experimental and modeling approach adopted. Many trade-offs driven by the need to balance economical operation against public/personnel safety must be made. When cost is the predominant driving force, engineering expediency leading to short-term solutions based only on qualitative assurances often dominate. Models for plant behavior must be based on accurate and realistic data to avoid unnecessary and costly shutdowns due to overly conservative predictions. Often, in this context, accurately measured but empirical data may be more valuable than a fundamen-... 

Figure 1 attempts to define the key stages in the development of corrosion models. Irrespective of whether the key concern is safety or operating efficiency, the steps involved in model development are common up to the point where data reliability must be accounted for (stage 8). At this juncture, the approaches deviate. When public/personnel safety is the key issue, one would adopt conservative assumptions (stage 9A) to cover the uncertainties that will inevitably permeate one s model. If plant efficiency is the key issue, then at this juncture it is necessary to refine one s data input by a combination of further experimentation and the careful consideration of information from plant inspection records (stage 9B). 

Mr. Ken Robertson, president of Exxon Chemical America, discussed protective programs or mechanical integrity programs in a keynote address at the Chemical Manufacturers Association s Plant Inspection and Maintenance Forum in 1990. Indicating that public expectations are increasing, Mr. Robertson noted that there is less tolerance for oil and chemical spills as well as tragic plant safety incidents. [7]... 

McGraw-Hill Publications has granted special permission to use excerpts from my ar-lide entitled Don t Leave Plant Safety to Chance," Chemical Engineering 9%, no. 2. February 1991. [8] Many paragraphs will be used verbatim in the rest of this section on SR Vs without being shown as quotes or without further reference. 

However, there have been cases where companies have hired unpredictable workers without a criminal record. In early 2004, in Texas, for example, a contract security guard at a BASF ammonia facility apparently shot himself, then blamed it on a foreign intruder, only to be arrested on other unrelated charges two weeks later. His story had been covered widely by the media, raising public concerns about plant safety. 

In case of any event that clearly deviates form normal behavior of a reactor (ranging from observations with safety implications to catastrophes), the event should be reported to IAEA and the appropriate organizations in other coimtries. For reports to the press and to the general public of safety related events in nuclear power plants IAEA and OECD/NEA recommend the INES scale, see Table 19.6. 

This Safety Guide supplements Section 6 of the Safety Requirements publication on the Safety of Nuclear Power Plants Operation [1], which relates to the maintenance, surveillance and in-service inspection of SSCs important to safety. It provides recommendations on the basis of international experience of measures for fulfilling the safety requirements for MS I. This publication supersedes the following three earlier IAEA Safety Guides In-service Inspection for Nuclear Power Plants, Safety Series No. 50-SG-O2 (1980), Maintenance of Nuclear Power Plants, Safety Series No. 50-SG-O7 (1990), and Surveillance of Items Important to Safety in Nuclear Power Plants, Safety Series No. 50-SG-O8 (1990). 

INES International Nuclear Event Scale INES is an information system operated by IAEA to inform the public about safety related events in nuclear power plants (IAEA 2001) http //www-news.iaea.org/news/... 

Consistent with these publications, the IAEA in 2002 issued a detailed report on Accident Analysis for Nuclear Power Plants (Safety Reports Series No. 23) that provides practical guidance for performing accident analysis. That report covers the steps required for accident analyses, i.e. selection of initiating events and acceptance criteria, selection of computer codes and modelling assumptions, preparation of input data and presentation of the calculation results. It also discusses aspects that need to be considered to ensure that the final accident analysis is of acceptable quality. Separate IAEA Safety Reports deal with specific features of individual reactor types, such as pressurized water reactors, boiling water reactors, pressurized heavy water reactors and RBMKs. 

This Safety Guide supplements the IAEA Safety Fundamentals publication The Safety of Nuclear Installations [1] and the Safety Requirements publication Safety of Nuclear Power Plants Operation [2]. It supersedes the Safety Guide issued as Safety Series No. 50-SG-O12, Periodic Safety Review of Operational Nuclear Power Plants, in 1994. 

The Safety Requirements publication entitled Safety of Nuclear Power Plants Design [1] states that a comprehensive safety assessment and an independent verification of the safety assessment shall be carried out before the design is submitted to the regulatory body (see paras 3.10-3.13). This publication provides guidance on how this requirement should be met. 

The Safety Requirements publication on Safety of Nuclear Power Plants Design [1] specifies that the following safety functions should be performed by associated plant systems on the assumption of a single failure ... 

The publication has been prepared by drawing on material from other IAEA publications. Particular benefit was gained from the work of the International Nuclear Safety Advisory Group (INSAG), and in particular its publication Basic Safety Principles for Nuclear Power Plants (IAEA Safety Series No. 75-INSAG-3). 

An IAEA publication on Safety Evaluation of Operating Nuclear Power Plants Built to Earlier Standards - A Common Basis for Judgement was issued in 1997 to provide details for the safety assessment and judgement process. This provides practical advice on the main judgements to be made in any review process of plant safety. 

INTERNATIONAL ATOMIC ENERGY AGENCY, Information to be submitted in support of licensing applications for nuclear power plants. Safety Series No. 50-SG-G2, Vienna (1979). Guideline for evaluation of PWR design during accident, 23, Abs.3, Public Notice, Federal Radiation Protection Ordinance No.245a, GRS, Dec. 1983, FRG. 

In consonance with those high level publications, this Safety Report provides more specific technical information on the implementation of this concept in the siting, design, construction and operation of nuclear power plants. It describes a method for comprehensive and balanced review of the provisions required for implementing defence in depth in existing plants. 

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