Albert Widmann with the car engine running. He had nearly died of carbon monoxide poisoning from the exhaust fumes. This engine exhaust testing inspired the development of gas vans. Back in Berlin, Reinhard Heydrich immediately set to work within the RSHA for the development of, in the words of Heydrich's subordinate Walter Rauff, a "more humane method of execution" than the "Einsatzgruppen" firing squads which had been used. When a prototype gas van was driven to KTI, Widmann explained to his young chemists that by adjusting the timing of the ignition, one could maximize the amount of poisonous carbon monoxide in the
Diesel exhaust oxygen is usually present to burn the fuel completely. (The oxygen requirement in non-idling engines is usually mitigated using turbocharging.). From the particle emission standpoint, exhaust from diesel vehicles has been reported to be significantly more harmful than those from petrol vehicles. Diesel exhausts, long known for their characteristic smells, changed significantly with the reduction of sulfur content of diesel fuel, and again when catalytic converters were introduced in exhaust systems. Even so, diesel exhausts continue to contain an array of inorganic and organic pollutants, in various classes, and in varying concentrations (see below), depending on fuel composition and engine