FUTURE TRENDS

In reviewing problem areas in data col le< t ion, a n a l y s i s and r e t r i e v a l the group of partir, i point s in the ir,M hay P id on t. if i ed the following aspects as deserving special attention by those- involved in col 1er t ing and using

r e l i a b i l i t y data. Some of the issues h i g h l ighted require further

invest igat ion and coordination of rese-ar ch in an international framework (o.g.

EAKA's Ooord inated Research Programme on Data Collection and A n a l y s i s for P S A) Da toi c o l l e c t e d in recent years have been done in a more systerna t J c way and are therefore to be preferred for use in r e l i a b i l i t y s t u d i e s . Historic«! record;» contain important <iuidence to be incorporated in data bases. It is however v/ery t i m e < onsuming to dig out informal ion in plant records cind to extract the r e q u i r e d data. In r e a l i t y , the effort does not always lead to usable results because of the way records haue been o r i g i n a l l y established.

Operating or exposure times arid number of demands are in many cases estimated to compensate for the J0icl< of actual records. I h i s procedure can 1ead to gross errors

h a i l u r e data collected does not r e f l e c t , in many Coises, hidden

dependencies between parts or components. Ft should be clearly stated in the data base, which data have been gathered assuming that f a i l u r e occurred independently.

Indication of the root causes of f a i l u r e s are an important source of information which can be used to unfold Hfpendencies.

1 he assumption that f a i l u r e rat.es c o l l e c t e d during tests of short duration are representative of longer operating times can be h i g h l y conservative, because f a i l u r e rates are normally higher in the i n i t i a l period of operation. Some preliminary studies indicate a factor of 10 difference, further work is needed in this area

Data c o l l e c t i o n is an expensive undertaking. ft is therefore of utmost importance that plant managers are convinced of the benefits of t h i s a c t i v i t y . Managers have to be given enough information on how

Manpower r equi renient s Tor data <.<>\ l ff. t ion art' j n general v e r y d i f f i c u l t to assess and can be misleading. Tor e x «imp i p, in some cases the actual number of poop]o stated to be i n v o l v e d ivi running the system can be low bfMause the involvement of the plant personnel needed is not reflected.

Different data bones may haue different structures depending on their specific o b j e c t i v e s , Tt is, however, important that common

r e q u i r e m e n t s are e s t a b l i s h e d to a l i o w for comrm.mication between data bases.

It is fur tlierrnore recommended that IM A wi J J use its i nternat ional role to lead an effort for constructing an international network of national and i n t e r n a t i o n a l data boises

Standardisation of information in data bases is highly desirable for sharing of i nternat jovial experi evice , Aspects which w i l l require standard]/ation include, for example, the failure description.

Countries embarking on re J iabi 1 i t_y data c o l l e c t i o n should take

advantage of the available international experience and should attempt to establish standard structure and content in the planning phase of thei r data bases.

T hit- aerospace <md m i J i t a r y industries report their failure records to a central)/ed data base. The available in for-mat ion is then shared among users for various purposes, i n c l u d i n g an alert system in cases when action has to be taken to prevent r occurrence of a reported failure.

An extension of some of the existing systems into the nuclear power f i e l d , should be considered.

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Appendix