It was assumed that the 50in. (1270mm) split occurred by zinc embrittlement and creep cavitation at high temperatures. This assumption was later confirmed by a metallurgical investigation showing that zinc embrittlement on austenitic stainless steel at a temperature of between 800 and 900 degree C could occur in a pipe under a stress of 3.21ton/sq.in. (48.8N/sq.mm) within a few seconds.