The Severe Reactor Accidents of Three Mile Island, Chernobyl, and Fukushima - The Risks of Nuclear Energy Technology - page 190

9.3.5.1 Comparison with the Safety Design of Other Nuclear Power
Reactors
The question whether the Fukushima-Daiichi accident scenario is also representa-
tive for other nuclear power plants in the world can be answered as follows:
Tsunami waves must only be expected for nuclear power reactors built near the
ocean. LWRs in Europe and the USA are designed against floods occurring once in
about 10,000 years, including waves, hurricanes, failure of dams, etc. (Chap. 7 ) .
Most of the presently operating nuclear power reactors in Europe and the USA
have similar safety design characteristics as pressurized water reactors and the
boiling water reactors described in Chap. 3 . These have a second emergency diesel
power grid system protected against airplane crash and other external events, which
ensures both cooling of the reactor core by way of the steam generators and cooling
of the fuel element pools. The emergency power building, like the regular emer-
gency power diesel buildings, is protected against flooding . The air intake open-
ings of the diesel generators are located in the upper region of the building
[ 20 ]. German pressurized and boiling water reactors—as an example—are
equipped with hydrogen recombiners (backfitting) which recombine the hydrogen
produced in accident situations within the inner containment. Boiling water reactors
have inner containments which are inertized by nitrogen. The containments of
pressurized water reactors in Germany—as an example—will resist to large scale
hydrogen detonations (Chap. 10 ).
Boiling water reactors have the appropriate emergency buildings with the same
functions as pressurized water reactors [ 20 ]. First of all, steam-driven turbopumps
are available for emergency core cooling. Then pressure relief is initiated, and the
inventory of the feed water tank—as an example in Germany—is passively fed into
the reactor pressure vessel. The reactor core can be cooled by means of mobile
pumps kept in the emergency building. There are several possibilities of feeding the
reactor core with water by mobile pumps up to and including pumps of the
firefighting system. The feed water reservoirs available include the demineralized
water tanks (tanks for water of very high purity), the drinking water system, internal
wells, and river water (severe accident management measures (Chap. 10 ) ).
9.3.6 Recommendations Drawn from the Fukushima
Accident
9.3.6.1 Recommendations of the American Nuclear Society Special
Committee on Fukushima
A committee of the American Nuclear Society with safety experts from the USA
and Japan made the following recommendations after thorough analysis of the
Fukushima accidents [ 21 ].