Containment design criteria

Containment enhancement provisions may also be part of a graded approach as augmentation or in I ieu of 10 CFR 50 containment design criteria. For an example, a filtered vented containment or confinement system may adequate protection to the public and onsite a containment heat removal system may not be reduce ultimate risk to an acceptable level, containment design criteria are used, the ultimate goal of protecting the health and safety of the public and onsite workers should be assured. 

Appendix A, Criterion 38 - Containment Heat Removal, and Criteria 39 and 40 - inspection and Testing of Containment Heat Removai Systems shouid be inciuded as part of the graded approach assessment for the overall containment design,... 

Criterion 52 - Capability for containment leakage rate testing. The reactor containment and other equipment which may be subjected to containment test conditions shall be designed so that periodic integrated leakage rate testing can be conducted at containment design pressure. 

Criterion 53 - Provisions for containment testing and inspection. The reactor containment shall be designed to permit (1) appropriate periodic inspection of all important areas, such as penetrations, (2) an appropriate surveillance program, and (3) periodic testing at containment design pressure of the leaktightness of penetrations which have resilient seals and expansion bellows. 

A. General Design Criterion 41 (Reference...) as it relates to containment atmosphere cleanup systems being designed to control fission product releases to the reactor containment following postulated accidents. 

Whilst some pipe users take pressure containment as their primary design criterion, others, notably the installers of large diameter pipes intended for low pressure drainage and sewerage, are far more concerned with design against failure by collapse or buckling... 

Fracture mechanics studies the effect of stress concentrations that occur when a load is applied to a body containing a void, independent of the geometry or material of the body. By this definition it would seem logical that the fracture toughness of a material, as determined by specific fracture mechanics techniques, would be an appropriate design criterion. 

Section 2.1 provided a discussion of design-basis accidents, as included in Chapter 15 of the Safety Analysis Report (SAR). For containments, the design must preclude exceedance of the 10 CFR 100 dose guidelines, given the most limiting accident evaluated in Chapter 15. Specifically, the requirements of 10 CFR 50, Appendix A, General Design Criterion 50 state ... 

Subsection A This subsection contains the general requirements applicable to all materials and methods of construction. Design temperature and pressure are defined here, and the loadings to be considered in design are specified. For stress failure and yielding, this section of the code uses the maximum-stress theory of failure as its criterion. 

Creep of polymers is a major design problem. The glass temperature Tq, for a polymer, is a criterion of creep-resistance, in much the way that is for a metal or a ceramic. For most polymers, is close to room temperature. Well below Tq, the polymer is a glass (often containing crystalline regions - Chapter 5) and is a brittle, elastic solid -rubber, cooled in liquid nitrogen, is an example. Above Tq the Van der Waals bonds within the polymer melt, and it becomes a rubber (if the polymer chains are cross-linked) or a viscous liquid (if they are not). Thermoplastics, which can be moulded when hot, are a simple example well below Tq they are elastic well above, they are viscous liquids, and flow like treacle. 

In Table III are shown values of p, p, X, n, SD, / and Hammett p values obtained for additional para BA type reaction series which contain data for sufficient numbers ( ) and kinds of substituents to provide a reasonably critical analysis. We do not believe, however, that the analysis is as critical for sets which do not meet the minimal requirements for a basis set. The reaction series are segregated according to type of measurement equilibrium, rate, and fluorine nmr (F-nmr) shift. Any data set in Table III and in all tables hereafter (other than designated basis sets) which meets our minimal basis set criterion is indicated by an asterisk. 

Another criterion for catalyst selection is relative comonomer incorporation. The proposed material design is one in which the soft segment (SS) is amorphous and the hard segment (HS) contains as little comonomer as possible. To achieve this combination, the chain shuttling catalysts must have very different reactivity ratios. 

One possible criterion for designating a compound complex , that the ligand is exclusively held by one metal, is too restrictive because it excludes the / -complexes. However, it is reasonable to state that if all anions contact more than three cations the solid does not contain complexed cations. Compounds made by addition of ligands to M(I)... 

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