Nuclear safety criteria

Nuclear Safety Criteria and Specifications for Space Nuclear Reactors, Dept, of energy. Document OSNP-1, Rev. 0, Washington, D.C. Dated Aug 1982,... 

ANS (1983) Nuclear safety criteria for the design of stationary PWR plants , ANSI/ANS 51.1. Bayliss, C. and Langley, K. (2003) Nuclear Decommissioning, Waste Management and Environmental Site Remediation. Elsevier. 

ANSI/ANS 51.1, "Nuclear Safety criteria for the Design of Stationary Pressurized Water Reactor Plants", 1983. 

N. Ketzlach, Bases for Establishing Nuclear Safety Criteria, Preprint V-35, Nuclear Engineering a Science Conference (1959). 

The SMPR designs now offered or proposed by the various suppliers satisfy the same nuclear safety criteria as the larger-slze units currently available, and therefore offer the same high level of nuclear safety. 

ANS 51.1 ANS 51.7 Nuclear safety criteria for the design of stationary pressurized water reactor plants Single failure criteria for PWR fluid systems... 

A quantitative analysis to assure that the probability of inadvertent nuclear detonation, inadvertent programmed launch, accidental motor ignition, inadvertent enabling, or inadvertent prearming meets the numerical requirements specified in applicable nuclear safety criteria documents. 

The safety classification methodology was derived from the standard, ANSI/ANS-51.1, "Nuclear Safety Criteria for the Design of Stationary Pressurized Water Reactor Plants" (Reference 2). The plan describes three safety-related classes and one nonnuclear safety class. The definitions for Safety Classes 1, 2, and 3 were found to comply with the standard definitions contained in 10 CFR 50.55a and NRC Regulatory Guide 1.26 (References 3 and 4). The definition for the nonnuclear safety class was included, but is outside the scope of this evaluation. 

F. R. Farmer, Reactor Safety and Siting A Proposed Risk Criterion, Nuclear Safety, Vol. 8, No. 6, Oak Ridge, TN, November-December 1967, pp. 539-548. 

Attributing the outmost importance to the safety factor was justified as regards nuclear and radiation hazardous objects all objects of the decommissioning and environmental rehabilitation pertained to that category. The safety criterion was also highlighted as the main factor for justification of priorities in the EBRD Terms of Reference for the SMP development. 

In order to facilitate the implementation of this nuclear safety design criterion DOE 5480.28, NATURAL PHENOMENA HAZARDS MITIGATION, specifies the requirements for each new and existing DOE facility. The evaluation criteria for this DOE Order are built around a graded approach. DOE 5480.28 specifies that an NPH analysis will be performed for all new and existing dOE faciI ities. Specifically ... 

Table I summarizes the results of seven KENO calculations. This table also includes the input parameters which were varied to make the calculations independent. The weighted average K-effective from these seven runs is 0.9303 with the standard deviation of the average being 0.0027. At the 95% confidence level, the actual K-effective, for which the calculated value is an approximation, lies below 0.936. ff the criterion for nuclear safety is that K-effective at the 95% confidence level be <0.950, then the weighted average of the seven runs would meet the safety criteria.

Farmer, F.R., Reactor Safety and Siting a Proposed Risk Criterion. Nuclear Safety (1967). 

Criterion 4. Fundamental safety functions Topic of toxic chemicals should he tied to nuclear safety (and) coolant inventory control should he a safety function. 

Criterion 50. Cleanup of reactor coolant Introduction of chemicals should be addressed in a manner tied to nuclear safety and radiological risk and should address chemical protection. 

With regard to employee performance evaluations, WSRC should ensure that performance evaluations for appropriate employees are based on nuclear safety dedication and include performance standards related to the maintenance of a positive safety culture attitude. Pending the above, acceptable satisfaction of this criterion remains an open item. 

Criterion 5 - Sharing of structures, systems, and components. Structures, systems, and components important to safety shall not be shared among nuclear power units unless it can be shown that such sharing will not significantly impair their ability to perform their safety functions, including, in the event of an accident in one unit, an orderly shutdown and cooldown of the remaining units. 

The nuclear reactor system, thanks to its reliability and to its inherent safety characteristics, may be installed in proximity of industrial and inhabited centres, while the design criterion of easy operation that characterises its circuits and its auxiliary systems extends its potential use to non-industrialised geographic areas, for which the needs for desalination is well known. 

The acceptance criterion for the resolution of GSI 103 is that the site chosen for a commercial nuclear generating facility shall be designed to accommodate a maximum expected flood from precipitation without jeopardizing the safe operation of the facility, in accordance with the guidance given in SRP 2.4.2, Rev. 3 and SRP 2.4.3, Rev. 3. Also, the facility design, including structures, systems, and components important to safety, shall meet the criteria specified in 10 CFR 50 Appendix A (GDC 2). 

In 1967, E R. Farmer of the United Kingdom proposed that the probabilities as well as consequences of potential accidents need to be estimated to assess the associated risk. Farmer used 1-131 as a surrogate for consequences. By plotting the probability and consequence of each postulated accident, one could distinguish those with high risk from those with low risk. He proposed a boundary line as a criterion for acceptable risk. Farmer s work was a conceptual breakthrough in nuclear reactor safety analysis. Farmer takes full credit as the originator and pioneer of PRA. 

The achievement of this policy was quantified in a probabilistic risk assessment (PRA) for the plant, judged against the frequency everity criterion recommended for a prototype reactor at a remote location. PRA was used throughout PFR s history to improve the quality of the safety arguments. The 1974 risk assessment was revised in 1984, and again in 1990 as part of the preparations for licensing of the AEA by the Nuclear Installations Inspectorate (Nil). 

Criterion 6. Design for a nuclear power plant Should minimize contamination of the facility. Reliance on passive systems or inherent features to perform fundamental safety functions should be emphasized. Design-basis threats (DBTs) should be included in the scope. 

Compliance with Appendix R has led to Despite the development of Criterion 3, fires significant improvements in fire safety at nuclear continued to occur at nuclear power plants. On... 

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