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Safety Control Criteria

There must be two safety control systems One of the systems, depending on the nature of the accident. Is to provide the primary protection the other, then, will function as a backup. The safety control systems must meet the following requirements  [Pg.95]

1) Both primary and backup system must have adequate strength to maintain the reactor subcrltical for all credible accidents at least until the reactor Is damaged beyond repair as a result of the causative accident. Beyond this point the Inserted safety control system or systems are required to maintain control only to the extent that the consequences of the incident are no worse than those which would resxilt from the causative accident alone. [Pg.95]

2 The primary system must have speed of control insertion adequate to (a) limit a power excursion from credible accidents which would In themselves result In damage, (loss of coolant, for example,) to one of a magnitude such that the ultimate consequences of the excursion are no worse than those which would have resulted from the causative accident alone, or (b) limit a power excturslon from other credible accidents (such as fast rod withdrawal) to one of a magnitude such that no damage beyond mild fuel stressing will result. [Pg.95]

The backup system must satisfy criterion (2) except It Is required to prevent fuel melting Instead of fuel damage  [Pg.95]


The operational control criteria and part of the safety control criteria are re-statements of the Hanford Total control Criterion As far as the operational control criteria are concerned the horizontal control rods have adequate strength in the operating reactor (minimum of 7 7 per cent cold) to control any fore-... [Pg.99]

The more restrictive criterion is the one dealing vith adequacy of control over various accident conditions. The first safety control criterion states that either control system must be able to maintain the reactor subcrltlcal for all credible accidents . ... [Pg.99]

The second safety control criterion is a restatement of the Hanford Speed-of-Control Criterion. Since the water-loss accident in N Reactor does not result in a rapid increase in reactivity as is the case in the present reactors, the accident... [Pg.99]

The second safety control criterion (Section 1.5.1.2) is a reatatsnent of the Hanford Speed-of Control Criterion. Since the water-loss accident in N Reactor does not result in a rapid increase in reactivity as is the case in the present reactors, the accident governing the response of the safety systems is one associated with rod-withdrawal. Since the horisontal rods combine both operational and safety functions, the limitation on withdrawal rate specified in the operational control criteria can alao be included in this discussion. [Pg.119]

With these four strategies comphance with Part 11 can be cost-effectively integrated into the management of any automated laboratory, and while primary consideration must be paid to compliance with requirements and to adding safety controls as necessary beyond those requirements, cost-effectiveness can appropriately be utdized as a third-level criterion in laboratory system selection, design, and management. [Pg.135]

In 1998 a Californian (MMWR, 2001) mother requested a blood lead level determination for her 18-month-old child. The result was a blood lead level (BLL) of 26 LLg/dl, which was well above the Center for Disease Control s (CDC) recommended criterion for clinical case management. It was subsequently found that the father had a BLL of 46 ( lg/dl, which was above the Occupational Safety and Health Administration (OSHA) requirement that workers with BLLs greater than 40 lg/dl receive additional medical examinations. Further testing found that his 4-month-old daughter had a BLL of 24 Rg/dl. This worker was employed in a company that refinished antique furniture, some of which was covered with lead-based paint. Subsequent testing of co-workers found that two refinishers had BLLs of 29 and 54 Rg/dl and four carpenters had BLLs of 46, 46, 47, and 56 ( lg/dl. A child in another family had a BLL of 16 ( lg/dl. What will be the long-term effects on the intellectual abilities of these children ... [Pg.87]

In the construction of the wet oxidation unit, several areas of safety were considered. Of utmost importance was that of personal safety. Since this type of operation demands the use of high pressures and temperatures, operator contact with the high pressure vessels had to be limited. To accommodate this criterion, a barrier was constructed to shield the operator from any unforeseen releases from the reactor. This barrier was constructed from 1/4 inch steel and is desig ied in a manner that will fully contain any releases. This barrier is also equipped with two explosion vents to direct the force of any explosions away from the main walls and into a safe area. To further maximize personnel safety, all operator assisted controls are mounted on the outside of the unit. [Pg.445]

A rationale for the inclusion or exclusion of impurities in a specification should be presented. The rationale should include a discussion of the impurity profiles observed in the safety and clinical development batches, together with a consideration of the impurity profile of batches manufactured by the proposed commercial process. Specified, identified impurities should be included along with specified, unidentified impurities estimated to be present at a level greater than the identification threshold given. For impurities known to be tmu-sually potent or that produce toxic or unexpected pharmacological effects, the quantification/detection limit of the analytical procedures should be commensurate with the level at which the impurities should be controlled. For unidentified impurities, the procedure used and assumptions made in establishing the level of the impurity should be clearly stated. Specified, unidentified impurities should be referred to by an appropriate qualitative analytical descriptive label (e.g., "unidentified A," "unidentified with relative retention of 0.9"). A general acceptance criterion of not more than the identification threshold for any unspecified impurity and an acceptance criterion for total impurities should be included. [Pg.319]

It is important that the tests employed detect bidirectional drug effects and be validated in both directions with appropriate reference (control) substances. This requirement is less appropriate for multiparameter procedures. Blind testing could be an advantage. Ethical considerations are important, but the ultimate ethical criterion is the assessment of risk for humans. Safety pharmacology studies should not be overly inclusive but should be performed to the most exacting standards, including GLP compliance. This is, of course, backward such human tolerance is properly an extension (and expression) of the nonclinical safety pharmacology. [Pg.195]

Criterion 3 - Fire protection. Structures, systems, and components important to safety shall be designed and located to minimize, consistent with other safety requirements, the probability and effect of fires and explosions. Noncombustible and heat resistant materials shall be used wherever practical throughout the unit, particularly in locations such as the containment and control room. Fire detection and fighting systems of appropriate capacity and capability shall be provided and designed to minimize the adverse effects of fires on structures, systems, and components important to safety. Firefighting systems shall be designed to assure that their rupture or inadvertent operation does not significantly impair the safety capability of these structures, systems, and components. [Pg.346]

Criterion 13 - Instrumentation and control. Instrumentation shall be provided to monitor variables and systems over their anticipated ranges for normal operation, for anticipated operational occurrences, and for accident conditions as appropriate to assure adequate safety, including those variables and systems that can affect the fission process, the integrity of the reactor core, the reactor coolant pressure boundary, and the containment and its associated systems. Appropriate controls shall be provided to maintain these variables and systems within prescribed operating ranges. [Pg.346]

Criterion 20 - Protection system functions. The protection system shall be designed (1) to initiate automatically the operation of appropriate systems including the reactivity control systems, to assure that specified acceptable fuel design limits are not exceeded as a result of anticipated operational occurrences and (2) to sense accident conditions and to initiate the operation of systems and components important to safety. [Pg.348]

Criterion 24 - Separation of protection and control systems. The protection system shall be separated from control systems to the extent that faUure of any single control system component or channel, or failure or removal from service of any single protection system component or channel which is common to the control and protection systems leaves intact a system satisfying all reliability, redundancy, and independence requirements of the protection system. Interconnection of the protection and control systems shall be limited so as to assure that safety is not significantly impaired. [Pg.348]

Criterion 29 - Protection against anticipated operational occurrences. The protection and reactivity control systems shall be designed to assure an extremely high probability of accomplishing their safety functions in the event of anticipated operational occurrences. [Pg.349]

The requirement for reducing the probability of reactor trip in the event of a loss of a single safety-related bus (criterion 2) is met by the System 80+ Standard Design, also as described in detail in CESSAR-DC, Section 8 3.2. As shown in CESSAR-DC, Figure 8.3.2-2, the safety-related (Class IE) DC power supply system consists of four separate isolated channels. The DC bus from each channel can be isolated from its battery bank and alternately supplied from its division s DC bus. For typical Class lE DC and AC instrumentation and control power supply systems, either the Channel A or Channel C DC bus can be supplied from the Division I, also a IE DC bus. Similarly, either the Channel B or Channel D bus can be supplied from the Division II, also a IE DC bus. Cross-ties between buses, however, are isolated through two sets of manually operated fusible disconnects. [Pg.234]

If pressure is redueed, the walls of the vessel will be exposed to less foree and the risk of explosion if the temperature increases will be lower. As a general criterion, API recommends the installation of devices able to reduce the pressure up to approximately 7 bar (relative) or up to half of the design pressure in 15 minutes. If the ground is sloped and the vessel is thermally insulated, this time can be longer. The depressurization can require a remote control valve besides the safety valve. The released material should be eliminated in safe conditions (Shebeko et al., 1996), e g., with a torch. It should also be taken into account that in some eases a strong depressurization ean cause extremely low temperatures, leading to fragile eonditions in the steel. [Pg.505]


See other pages where Safety Control Criteria is mentioned: [Pg.95]    [Pg.5]    [Pg.111]    [Pg.269]    [Pg.2]    [Pg.32]    [Pg.79]    [Pg.738]    [Pg.302]    [Pg.1143]    [Pg.42]    [Pg.165]    [Pg.319]    [Pg.704]    [Pg.280]    [Pg.6]    [Pg.185]    [Pg.61]    [Pg.376]    [Pg.80]    [Pg.345]    [Pg.347]    [Pg.353]    [Pg.8]    [Pg.87]    [Pg.124]    [Pg.1814]    [Pg.136]    [Pg.364]    [Pg.158]    [Pg.247]    [Pg.512]    [Pg.6]    [Pg.101]    [Pg.58]    [Pg.273]    [Pg.106]    [Pg.739]   


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