This paper briefly describes the codes used for International Thermonuclear
Experimental Reactor (ITER) safety analysis, including some information on
their validation status, and summarizes some examples of validation and ve
rification (V&V). V&V information is provided for the codes involved in acc
ident analyses dealing with water coolant ingress into the vacuum vessel. R
esults obtained by the MELCOR and INTRA codes, and the ISAS system, are com
pared with the test results of the integrated ICE facility simulating water
coolant ingress into the vacuum vessel. Benchmark calculation results of t
he MELCOR, INTRA, and ISAS were compared with the results from other codes
like PAX, CONSEN, TRAC-BF1, CATHARE. (C) 2001 Elsevier Science B.V. All rig
hts reserved.