I decided to design and build a crematorium with a higher capacity. I completed this project of a new crematorium in November 1942 - a crematorium for mass incineration, and I submitted this project to a State Patent Commission in Berlin.
This "Krema" was to be built on the conveyor belt principle. That is to say, the corpses must be brought to the incineration furnaces without interruption. When the corpses are pushed into the furnaces, they fall onto a grate, and then slide into the furnace and are incinerated. The corpses serve at the same time as fuel for heating of the furnaces. This patent could not yet be approved by the Main Patent Office in Berlin, because of its classification (as a state secret).
Q. Although you knew about the mass liquidation of innocent human beings in crematoriums, you devoted yourself to designing and creating higher capacity incineration furnaces for crematoriums - and on your own initiative.
A. I was a German engineer and key member of the Topf works and I saw it as my duty to apply my specialist knowledge in this way to help Germany win the war, just as an aircraft construction engineer builds airplanes in wartime, which are also connected with the destruction of human beings.
Sources: Quoted from the interrogation transcripts by Prof. Gerald Fleming from the University of Surrey, New York Times, (July 18 1993). The Nizkor Project