Click here to make tpub.com your Home Page

Page Title: Determination of Preliminary Performance Category for NPH-Related Safety System Components
Back | Up | Next

Click here for thousands of PDF manuals

Google


Web
www.tpub.com

Home

   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Logistics
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
   
   

 



DOE-STD-1021-93
Safety systems whose columns have one or more entries are then identified as the NPH related safety
systems of the facility.
Thus, for the purpose of performance categorization, the entire facility can be divided into three
groups of systems:
Group I:
Safety systems (see Section 2-3) that must function during and/or after an NPH
event.
Group II:
Safety systems not in Group I above.
Group III:
Other systems that do not perform any safety function by themselves,
Components in Group I systems that perform any of the safety functions listed above will be
preliminarily placed in PC-4, PC-3, or PC-2, according to the basic categorization guidelines of
Subsection 2.4 and using the procedures described in Subsection 3.5 below. Other components in
Group I systems that, using graded approach, do not belong there, along with the components in
Group II and Group III systems, will be preliminarily placed in PC-2, PC-I, or PC-0, according to
the criteria of Subsection 2.4 and using the procedures described in Subsection 3.6 below, unless
they are placed in higher performance categories for improved performance (see Section 2.1[d]).
These preliminary performance categories will then be modified to account for potential system
interaction effects, in accordance with the guidelines given in Subsection 2.5 and using the
procedures given in Subsections 3.7 and 3.8 below.
3.5
Determination of Preliminary Performance Category for NPH-Related Safety System
Components
The components of the NPH-related safety systems (i.e., Group I systems) can be preliminarily
categorized according to the guidelines provided in Subsection 2.4 and using one of the three methods
presented below. The methods are presented in order of increasing rigor or decreasing conservatism.
Following the "graded approach" philosophy, the method to be used should be selected on the basis
of cost-benefit considerations. The end result of this step will be a preliminary performance category
list for the NPH-related safety system components of the facility.
(a)
Method 1: System-by-System Categorization
In this method, the performance category of a given component of a safety system (identified
by an entry in the safety system-function matrix, see Table 3-1) will be the same as the
highest performance category applicable to any component of the system per Subsection 2.4
guidelines, irrespective of the safety function of the particular component. Thus, all the
components of a system will have the same performance category. This is the most
conservative of the three methods and the only applicable method if the safety function of only
the entire system is known, and information on the safety function of individual components
of the system is unavailable. This method is preferable in the following situations:
(i)
To select an initial performance category that can be used to determine the preliminary
design hazard level (e.g., seismic acceleration level) for the component. If the
3-5


Privacy Statement - Press Release - Copyright Information. - Contact Us

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business