Personal effects taken from the prisoners at Auschwitz before they were taken to the gas chamber.

Gassing Operations

The Nazis killed millions of people in gas vans or in stationary gas chambers. The victims were people with disabilities and later Jews and other prisoners. The vast majority of those killed by gassing were Jews.  

Key Facts

  • 1

    The six killing facilities in the Euthanasia Program used gas chambers, disguised as shower facilities,to kill patients with pure chemically manufactured carbon monoxide gas.

  • 2

    Gas vans with carbon monoxide exhaust piped into the passenger compartment were used by killing squads in the east and at the Chelmno killing center.

  • 3

    Gas chambers were installed at many camps. At the five killing centers, either carbon monoxide or a pesticide, Zyklon B, was used for mass murder.

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The Nazis began experimenting with poison gas for the purpose of mass murder in late 1939 with the killing of patients with mental and physical disabilities in the Euthanasia Program.

Euthanasia Program

Helene Melanie Lebel

The elder of two daughters born to a Jewish father and a Catholic mother, Helene was raised as a Catholic in Vienna. Her father died in action during World War I when Helene was just 5 years old, and her mother remarried when Helene was 15. Known affectionately as Helly, Helene loved to swim and go to the opera. After finishing her secondary education she entered law school.

1933-39: At 19 Helene first showed signs of mental illness. Her condition worsened during 1934, and by 1935 she had to give up her law studies and her job as a legal secretary. After losing her trusted fox terrier, Lydi, she suffered a major breakdown. She was diagnosed as schizophrenic, and was placed in Vienna's Steinhof Psychiatric Hospital. Two years later, in March 1938, the Germans annexed Austria to Germany.

1940: Helene was confined in Steinhof and was not allowed home even though her condition had improved. Her parents were led to believe that she would soon be released. Instead, Helene's mother was informed in August that Helene had been transferred to a hospital in Niedernhart, just across the border in Bavaria. In fact, Helene was transferred to a converted prison in Brandenburg, Germany, where she was undressed, subjected to a physical examination, and then led into a shower room.

Helene was one of 9,772 persons gassed that year in the Brandenburg "euthanasia" center. She was officially listed as dying in her room of "acute schizophrenic excitement."

A Nazi euphemism, "euthanasia" referred to the systematic killing of those Germans whom the Nazis deemed "unworthy of life" because of mental illness or physical disability.

Six gassing installations were established as part of the Euthanasia Program: Bernburg, Brandenburg, Grafeneck, Hadamar, Hartheim, and Sonnenstein. These killing centers used pure, chemically manufactured carbon monoxide gas.

Gas Vans

After the June 1941 German invasion of the Soviet Union and Einsatzgruppe mass shootings of civilians, the Nazis experimented with gas vans for mass killing. Gas vans were hermetically sealed trucks with engine exhaust diverted to the interior compartment. Use of gas vans began after Einsatzgruppe members complained of battle fatigue and mental anguish caused by shooting large numbers of women and children. Gassing also proved to be less costly. Einsatzgruppen gassed hundreds of thousands of people, mostly Jews, Roma (Gypsies), and mentally ill people.

Killing Centers

Chelmno

In 1941, the SS concluded that the deportation of Jews to killing centers (to be gassed) was the most efficient way of achieving the "Final Solution." That same year, the Nazis opened the Chelmno camp in German-occupied Poland. Jews from the Lodz area of German-occupied Poland and Roma were killed there in mobile gas vans. 

Belzec, Sobibor, and Treblinka

In 1942, systematic mass killing in stationary gas chambers began at Belzec, Sobibor, and Treblinka, all in German-occupied Poland. These gas chambers used carbon monoxide gas generated by diesel engines. As victims were "unloaded" from cattle cars, they were told that they had to be disinfected in "showers." The Nazi and Ukrainian guards sometimes shouted at and beat the victims, who were ordered to enter the "showers" with raised arms to allow as many people as possible to fit into the gas chambers. The tighter the gas chambers were packed, the faster the victims suffocated. 

Auschwitz

The Nazis constantly searched for more efficient means of extermination. At the Auschwitz camp in German-occupied Poland, they conducted experiments with Zyklon B (previously used for fumigation) by gassing some 600 Soviet prisoners of war and 250 ill prisoners in September 1941. Zyklon B pellets converted to lethal gas when exposed to air. They proved the quickest gassing method and were chosen as the means of mass murder at Auschwitz.

At the height of the deportations in 1943–44, an average of 6,000 Jews were gassed each day at Auschwitz.

Concentration Camps

Concentration camps like Stutthof, Mauthausen, Sachsenhausen, and Ravensbrück, although not designed specifically as killing centers, also had gas chambers. The gas chambers were relatively small, constructed to kill those prisoners the Nazis deemed "unfit" to work. Most of these camps used Zyklon B as the killing agent in their gas chambers.

Critical Thinking Questions

  • How were the operations against people with disabilities similar or dissimilar to the gassing of the Jews in the Final Solution?

  • Why did the mass killing operations switch to more centralized and stationary operations?

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Glossary