During the selection made by Nazi doctors to separate deportees deemed fit to work from those "useless", who were immediately sent to the gas chambers, Venezia was saved along with his brother Maurice (Morris) and two cousins.
During his imprisonment he was forced to work in the Sonderkommando ("special units"), teams of inmates that dealt with disposal and cremation of the prisoners killed in gas chambers.
Venezia was subjected to the typical procedure of the deported to Auschwitz: shaving, showering, being tattooed with a number on the left forearm, and wearing the interned uniform.
As a guest on television, in schools, and at memorial events for the Holocaust, he turned his interest to young people as future spokespersons of the immense tragedy that struck Europe between 1940 and 1945.
[5] Shlomo features throughout Auschwitz - The Final Witness, a 2001 NY Festival winning film made by Sky for Channel 5, which reunited him with his Sonderkommando brother and cousin as they revisited the death camp together for the first time in over 50 years.