Operational Feedback

Typical problems that have been encountered in various projects relate to the following areas  

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Although the issue of PIF interactions has long been recognized by human factors researchers, little has been done to develop practical recommendations. This is partially a result of the large number of possible PIF combinations and the complexity of their interactions. One of the most effective ways of studying this interaction is through an in-company human factors study which will use operational feedback to evaluate the results of design and human factors innovations. 

This is in contrast to many data collection systems, in which considerable efforts are expended in developing a "definitive" data collection philosophy. However, once the system is in place, there is little attempt to modify this on the basis of operational feedback. 

In the preceding chapters we investigated the basic patterns of behaviour which might be exhibited by a reaction scheme which involved a certain form of chemical feedback under isothermal conditions. Here we make a similar analysis for systems with purely first-order chemical reactions but under conditions in which the heat produced by the natural exothermicity can lead to departures from isothermal operation. Feedback is then provided from thermal coupling as the increase in temperature of the reacting mixture leads to an increase in the local value of the reaction rate constant. 

Traditional Performance overview achievable One to one review Records easily kept Action plans made Training needs identified Simple to operate Feedback can be one way Authoritarian temptation for managers Daunting if staff differential too large... 

The process should be continuous, capable of control by metering the inactive feeds, free from the necessity of relying on process control instrumentation operating feedback loops, and have a slow response time to variations in conditions to enable the necessary monitoring instruments (temperature, concentration, fiow rates and radioactivity) to establish trends so that corrective action may be taken carefully before the product and waste qualities are affected significantly. 

Cost reduction and reliability improvement studies have been performed to select the steam generator concept for EFR. An integral unit of 600MW(th) has been verified as favourable based on successful operating feedback from the SPX SGs. The advanced SG for EFR is a once-through straight-tube unit, without welds in the long (33,3m) tubes with tube to the tubeplates weld at each end. 

Since 1995, a systematic approach to check the design of the EFR systems has been carried out in the framework of the Project Reviews of the main systems and components based on operating feedback. 

Operating feedback of the same or similar systems from plants in operation (or having been operated). 

Concerning the "principle design sheet", there are no particular remarks from the operating feedback integrated electro-magnetic pumps at Superphenix are reliable an external circuit makes maintenance operations easy. 

Hence it has been suggested that the EFR argon reactor cover gas circuit design return to a (almost) constant pressure circuit, bringing benefits from operating feedback. 

The helical steam generator design can be considered favourably based on the Superphenix operating feedback. 

Operational feedback on trends, incidents, and accidents should trigger reanalysis when appropriate. Linking the assumptions throughout the document with the parts of the hazard analysis based on that assumption will assist in performing safety maintenance activities. 

Regularize and improve communication channels. Create the operational feedback channels from controlled components to controllers necessary to maintain accurate process models to assist in safety-related decision making. If the channels exist but are not used, then the reason why they are unused should be determined and appropriate changes made. 

French and international operational feedback (Generic Letter dated 17 October 1988 from the USNRC) ... 

Holy J. Some insights from recent applications of HRA methods in PSA effort and plant operation feedback in Cezech Republic. 2004. Rel. Eng. and Systems Safety. 169-177. 

Operating experience This source results from a thorough review of the operational feedback from experience collected by the nuclear industry worldwide and application of engineering judgement. All pertinent events should be evaluated in the definition of the scope of EOPs. Examples include ... 

Continuous simulator training obviously keeps the operators at a higher level of proficiency in the use of EOPs but an added benefit that will be realized is operator feedback on the EOPs. This feedback can have many forms but some of the more common ones are suggestions on improving EOF ergonomics and improvement in EOF strategies. Incorporation of relevant operator feedback is important since these improvements assure the operators that the EOPs are their procedures . 

The plant Safety Analysis Report, updated in 1996, the operational documentation and the operational feedback database were used as background documents for the review. In addition, the results of a PSA Level 1 study developed for full power, low power and shutdown operational regimes were available for the review, as well as specific analyses of internal flooding and fires. Plant design documentation was also used to an appropriate extent. However, it should be emphasized that due to the hmited scope and time available for the review, the objectives of the screening were more related to verification of the applicabihty of the approach than to evaluation of the safety status of the plant. Therefore, this section cannot be considered as a formal safety review of the plant. 

The dependency between a class of components and/or various redundancies is modeled via classical common cause factors, using international best practices (alpha model) and data implementing operational feedback. 

Future designs should take into account the operational feedback from maintenance activities in order to determine shielding requirements and design for ALARA. In addition, further improvement shall be made to reduce internal radiation dose. The use of more efficient vapour recovery dryers, the separation of reactor coolant and moderator support systems, and the separation of ventilation to the moderator heavy water management area are examples of improvements which will help to meet the objective of reducing occupational dose to plant persoimel. 

The controlled driving cycles allow manufactnrers to gain quality performance and operation feedback that will enable further system improvement. 

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