Teachin g Notes

Operationa l Reacto r Safet y Course

Lecture : 2 0 – Chernobyl

Objective :

The m a in objective of this lecture is to have students understand what happened at Chernobyl with the point of showing that en gineering and design m a tter particularly in the core design. This lecture should dem ons trate how bad things can get without proper vigilance in design and operat ions. A com parison with TMI is m a de. Most of these slides com e from an IN PO presentation on Chernobyl.

Ke y Point s t o Brin g Out:

Slid e num be r Point s

2-5 Describe the location and layout of the Chernobyl plant. Key Points to bring out are the comm on turbine ha ll a nd large rea ctor size.

6-9 Discuss basic plant design - pre ssure tube boiling water reactor - large core w hich poses neutronic coupling issues as does the graphite m o derator.

10-14 Photos illustrating larg e reacto r components and control roo m

that is also large with m any indica to rs tha t are d i f f i cult to m o nitor.

15-17 Review detailed cons equ e nces acco rding to the tim e line and violations of procedures for this test. Discuss role of xenon, tim ing of test, im plications of delay in test sequence, operator knowledge of reactor.

18-33 Show photos of consequences of Chernobyl including what happens when a core m e lts and the energy stored in the core.

34 Known design issues should be e xplained to future nuclear engineers. Each should be describe d to gain an appreciation of its significance. Explore why a plant would be designed like this?

35 Review causes of Chernobyl to be sure students can correlate the

cause to a design or procedural e rror. Begin to introduce the role of saf ety culture. Reca ll all nuc l ear o p erato r s were colleg e degreed people.

36-37 Even though the design of Ch ernobyl and TMI are quite different, both had m e ltdowns - w hy? This slide shows that a com bination of design and training issues we re a common cause. Focus on a lack of a questioning attitude.

38-42 Review consequences o f the Chernobyl accid e nt on the future of nuclear energy, econom i c consequences in Russia, contam ination, and Russia' s energy supply. Discuss im prove m e nts m a de to keep som e of the RBMKs operating. The 4 Chernobyl plants have now been shutdown.

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22.091 / 22.903 Nuclear Reactor Safety

Spring 200 8

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