The Gas Chamber Capacity is Physically Impossible

This claim purports to do an engineering calculation. It compares a published throughput figure (often the figure of 12,000 to 24,000 killed per day at Auschwitz during the peak Hungarian deportations of summer 1944) with a calculated chamber capacity and concludes the figures cannot reconcile. The calculation is wrong on its inputs. The denier figures for chamber capacity are deliberately conservative, the figures for cremation capacity ignore the open-pit burning that supplemented the ovens at peak periods, and the figures for ventilation are drawn from peacetime industrial standards rather than from the actual SS practice of opening the doors to the outside air rather than waiting for forced ventilation. The actual operational record at Auschwitz in summer 1944, taken from SS reports, Sonderkommando testimony, and the surviving aerial photographs, is consistent with the throughput claims.

The capacity of the chambers

The four large gas chambers at Birkenau (in crematoria II, III, IV and V) had different floor areas. The two large below-ground chambers in crematoria II and III each had a floor area of approximately 210 square metres. The two surface chambers in crematoria IV and V were smaller, divided into multiple rooms, with a combined floor area for each crematorium of approximately 240 square metres. The earlier converted-farmhouse chambers, the so-called Bunker I and Bunker II, had floor areas of approximately 90 and 105 square metres respectively. The total killing-chamber floor area available at Birkenau in May to July 1944 was approximately 950 square metres.

The denier calculations assume one person per square metre, which is the spacing for, say, a standing crowd at a religious service. The actual loading of the chambers, described by every Sonderkommando witness and by Höss in his memoir, packed people in to the point where the doors had to be forced shut. Höss specifically described “1,500 to 2,000” people in chamber II at a single gassing, in a chamber whose nominal area was 210 square metres. That is between seven and ten people per square metre, achieved by physical compression, with people standing pressed against each other in conditions that would be unbearable for any duration. They did not have to be bearable for any duration. They had to last twenty minutes. The Sonderkommando accounts describe the bodies being entangled when the doors were opened, the people having tried to climb over each other towards the air at the top of the room. The SS knew exactly how the chamber loaded and how the people died. The denier calculation that assumes a comfortable crowd density is calculating the wrong thing.

The cremation capacity

The cremation capacity of the four crematoria has been calculated repeatedly. The Topf und Söhne specification for the muffle ovens in crematoria II and III gave a daily capacity of approximately 1,440 bodies between the two facilities operating at full design rate. The smaller crematoria IV and V together were rated at approximately 1,500 bodies per day. The Birkenau cremation capacity at design rate was therefore approximately 4,400 bodies per day, sustained continuously. The deniers cite the design rate as a maximum and argue that the killing rates ascribed to the camp at peak (12,000 per day) cannot have been processed because they exceed the cremation capacity by nearly threefold.

The argument fails because the peak-period killing was not entirely processed through the ovens. The Hungarian deportations of May to July 1944 brought approximately 437,000 Jews to Auschwitz in fifty-six days. The cremation ovens, operating well above their design rate, processed some of the dead. The rest were burned in open pits dug behind crematoria IV and V and beside Bunker II. The pit burning is documented in the surviving SS communications, in the Sonderkommando manuscripts buried at the crematoria (Gradowski’s account is particularly detailed), in the testimony of Filip Müller and other survivors, and in the Allied aerial reconnaissance photographs of June, July, August and September 1944, which show the open burning pits clearly visible from 30,000 feet. The smoke from the pits was reported by Allied intelligence at the time. The technique was a deliberate response to the cremation capacity being insufficient for the killing rate; the SS solved the problem by adding open-air burning to the oven cremation.

Ventilation

The denier ventilation argument assumes that the chambers had to be cleared of cyanide gas to safe industrial concentrations before the doors could be opened, citing peacetime German industrial standards of approximately twenty minutes ventilation time. This was not the SS practice. The Sonderkommando described, and the Topf documentation confirms, that after the gassing the SS opened the doors to the outside air and waited only the few minutes necessary for the gas concentration to fall to a level where Sonderkommando workers wearing gas masks could enter. The workers’ own safety was not a constraint that the SS gave priority to. The chambers were ventilated by a combination of the forced extractor fans (for which the construction documents survive) and the simple expedient of the door being open. The ventilation was fast enough, and the documents and testimony agree about the timing.

Why the claim is harmful

The throughput-impossibility argument is harmful because it borrows the cultural authority of an engineering calculation while making the calculation badly. It uses the wrong loading density, ignores the open-pit burning, and assumes ventilation standards the SS did not in fact observe. To accept the denial, one would have to dismiss the Sonderkommando testimony, the Höss memoir, the Topf operational records, the Allied reconnaissance photographs of the pits, the testimony of perpetrators at trial, and the Hungarian transport records that document approximately 437,000 arrivals in fifty-six days. The arithmetic the deniers do is selective; the arithmetic the records actually support is consistent.

What loading density did the SS use, on whose testimony? Where did the bodies that the ovens could not process actually go? What do the aerial photographs show?

See also

• The Sonderkommando
• Cremation Capacity Was Insufficient for Six Million
• Rudolf Höss
• The Hungarian Deportations 1944

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Sources

• Topf und Söhne, design and operational specifications for the cremation ovens at Auschwitz crematoria II, III, IV and V, Thuringian Main State Archive, Weimar, with parallel correspondence in the Russian State Military Archive, Moscow, fond 502
• Jean-Claude Pressac, Auschwitz: Technique and Operation of the Gas Chambers, Beate Klarsfeld Foundation, 1989, with full reproduction of the construction drawings and operational data
• Franciszek Piper, “Gas Chambers and Crematoria”, in Yisrael Gutman and Michael Berenbaum (eds.), Anatomy of the Auschwitz Death Camp, Indiana University Press / USHMM, 1994
• Allied aerial reconnaissance photographs of Auschwitz-Birkenau, June, July, August and September 1944, US National Archives, College Park, Record Group 373; analysis in Dino A. Brugioni and Robert G. Poirier, The Holocaust Revisited: A Retrospective Analysis of the Auschwitz-Birkenau Extermination Complex, Central Intelligence Agency, 1979
• Rudolf Höss, Kommandant in Auschwitz, edited by Martin Broszat, Deutsche Verlags-Anstalt, 1958, with the loading-density description
• Filip Müller, Eyewitness Auschwitz: Three Years in the Gas Chambers, Stein and Day, 1979, with the operational sequence and the open-pit burning
• Henryk Tauber, deposition to the Polish judicial commission, 24 May 1945, in Pressac, Auschwitz: Technique and Operation
• Zalmen Gradowski, manuscript recovered from the Birkenau crematorium grounds, in Jadwiga Bezwińska and Danuta Czech (eds.), Amidst a Nightmare of Crime: Manuscripts of Members of Sonderkommando, Auschwitz-Birkenau State Museum, 1973
• Robert Jan van Pelt, The Case for Auschwitz: Evidence from the Irving Trial, Indiana University Press, 2002, with the throughput calculations and refutation of the denier engineering arguments
• Mr Justice Charles Gray, judgment in David Irving v. Penguin Books and Deborah Lipstadt, Royal Courts of Justice, 11 April 2000, on the throughput calculations
• Randolph L. Braham, The Politics of Genocide: The Holocaust in Hungary, condensed edition, Wayne State University Press, 2000, with the Hungarian deportation records and arrival rates
• Auschwitz-Birkenau State Museum, “Crematoria and Gas Chambers”, https://www.auschwitz.org