The Alleged Experimental Gassings at Belzec

Published: 2008-09-10

The testimony of Stanislaw Kozak

Stanislaw Kozak, a locksmith, was one of twenty Bełżec locals who participated in the construction of the alleged extermination camp to the south-east of this small Polish community. On October 14, 1945, Kozak was interrogated by the regional investigative judge Czeslaw Godzieszewski. According to his testimony, Kozak and the other villagers worked from November 1 to December 22, 1941 with the construction of three barracks of varying sizes. The structure of the third and smallest barrack, which by orthodox historians has been identified as the alleged first gas chamber building, is described thus by Kozak:

It was split into three rooms by wooden walls, each room thus measuring 4 by 8 meters; they were 2 meters high. The dividing walls were made of wooden boards nailed to either side, the space in between being filled with sand. On the inside, the walls of the barrack were covered with cardboard; the floors and the walls up to a height of 1 m and 10 cm were covered with sheets of galvanized steel. [… T]here were three doors for access to the three parts of the barrack. Each part had a door on the northern side, about 1.80 m high and about 1.10 m wide. These doors, as well as those from the corridor, were tightly sealed with rubber. All the doors of this barrack opened toward the outside. The doors were very strong, made from planks three inches thick and protected against being pushed open by a wooden bolt that would be placed into two hooks specially mounted for this purpose.[1]

Since Kozak's account is remarkably detailed when dealing with the "gas chamber building" it is of much interest to anyone who seeks to understand what really went on in the Bełżec "death camp".

In the following article, I will discuss the implications the Kozak account as well as other pieces eyewitness testimony has for the allegations that experimental gassings with bottled carbon monoxide and Zyklon B were carried out in the first Bełżec "gas chambers."

The revisionist interpretation of the ovens

Perhaps the most controversial aspect of the Kozak testimony concerns the three ovens which the witness reports to have helped install inside the three "gas chambers." Before I commence with my remarks, I will quote the relevant part of the testimony in order to make my argument more understandable. Here follows the abovementioned passage:

Each of the three rooms had water pipes at a level of 10 cm above the floor. Furthermore, on the western wall of each part of the barrack water pipes ascended vertically to a level 1 m above the floor, ending with an opening directed into the room. The elbowed pipes on the walls of the barrack were connected to the pipes running below the floor. In each of the three parts of the shed we set up ovens weighing about 250 kilograms. One may assume that the elbowed pipes were later connected to the ovens. The ovens were 1 m 10 cm high, 55 m wide and 55 cm deep. Out of curiosity I looked into an oven through the oven door. I did not see any grids. The inside of the oven seemed to be lined with refractory bricks. I did not see any other openings. The oven door was oval in shape and had a diameter of some 25 cm placed about 50 cm above the floor.[2]

Revisionists have pointed out that the ovens described constitutes a remarkable anomaly, i.e. they are not objects which one would expect to find in a homicidal gas chamber. Revisionist historian Carlo Mattogno concludes that the ovens were in fact Heißluftentwesungsöfen , or hot air disinfestations ovens, however without providing any further documentation backing up this claim.[3]Mattogno has on the other hand written of a more sophisticated hot air disinfestation facility at Majdanek:

As per this project, the eight delousing chambers were each 2 m wide, 2.10 m high and 3.5 m long and were heated with a coke-fueled calorifer or air heater located between each pair of chambers behind the outside walls. On the inside an opening in the top, connected to the air heater, allowed warm air to exit; on the opposite side, on the floor of each pair of chambers, was a ventilation opening also connected to the air heater via an underground air channel. In structural terms the facility was very similar to the model designed by Kori on July 5, 1940, for the delousing facility of Alt-Drewitz. Delousing proceeded not with Zyklon B, but with hot air.[4]

French researcher Jean-Claude Pressac, who otherwise believed (or professed to believe) in the existence of Nazi homicidal gas chamber published a paper in 1995 in which he proposed that the three Reinhardt camps (Bełżec, Sobibór and Treblinka) had originally been delousing and transit facilities, which were only later equipped with installations for mass killing. The same article makes it implicit that the ovens described by Kozak were part of a delousing system which utilized steam or hot air.[5]

The exterminationist interpretation of the ovens

It is noteworthy that Yitzhak Arad, the foremost orthodox authority on the subject of the Aktion Reinhardt "death camps," in his standard work on said camps quotes a large portion of Kozak's testimony, including the description of the ovens, without providing any comment, however brief, on the presence of the latter.

Later exterminationist writing, and especially that of online-based anti-revisionists, has apparently felt it necessary to address the issue. Their standard way of tackling the issue of the three ovens - as well as the fact that Kozak does not mention any kind of gassing engine or other sort of lethal gas - is to claim that the first months of the camp's existence constituted an experiment phase when bottled carbon monoxide (and perhaps even Zyklon B according to some rare sources) was used as killing agent, rather than exhaust gas from some type of engine. The ovens, it is alleged, served to

...heat the shed's rooms, thus allowing the bottled gas and Zyklon B used in the early stage of the camps' killing activities to work more efficiently in cold weather.[6]

The idea that bottled CO was used for the homicidal gassings appears to be exclusively grounded in the post-war testimony of former Bełżec SS man Josef Oberhauser, who stated that:

During the first experiments and the first set of transports in the second series of experiments bottled gas was still used for the gassing however, for the last transports of the second series of experiments the Jews were killed with the exhaust gas from a tank or lorry engine which was operated by Hackenholt.[7]

The claim of Zyklon B gassings likewise originate with Josef Oberhauser. The victims were allegedly the Jews who had worked with building the camp.[8]

Would the ovens described by Kozak really have been appropriate for, or even compatible with, the above described uses? This is the question I will take up in the following parts of this article.

The alleged gassings with bottled carbon monoxide

A safety brochure entitled Carbon Monoxide in the Work Place and issued by the Canadian Industrial Accident Prevention Association (IAPA) informs us about the following characteristics of carbon monoxide gas (italics mine):

Carbon monoxide is flammable. Mixtures of carbon monoxide and air in the flammable range will ignite if a flame or spark is present. Flammable mixtures containing carbon monoxide and other gases can be ignited easily by heated surfaces , open flames and even by the burning tip of a cigarette. The serious nature of the flammability hazard is reflected in the extensive flammable range of carbon monoxide in the air.[9]

The same source gives the flammable range (in air by volume) for carbon monoxide as 12.5 - 74 %, for sure a very extensive range. It also warns of attempts to put out fires involving carbon monoxide unless the flow of gas can be stopped, since a more explosive mix of air and gas may form.

If the purpose with heating the "gas chambers" really had been to make gassings with Zyklon B and bottled CO during cold weather more efficient, one would have used small portable braziers that could be easily carried in and out of the rooms prior to the gassing. There would have been no reason to use the 250 kilogram heavy ovens connected to piping that Kozak describes. Since such ovens could not easily have been removed from the chambers immediately prior to the gassings (and then moved back in afterwards!), we have to assume that they were still inside the chambers when the victims were led in. But if the ovens had been used prior to the gassing, then there would be the risk of the oven's heated metal surfaces or still glowing remains of fuel igniting the mixture of carbon monoxide and air.

The extensive piping work in the chambers, as described by Kozak, in fact belies the assertion that the ovens were used for heating up the air prior to gassings. Since the air in this case would only need to be raised to about room temperature or slightly above that, portable braziers would have been fully sufficient even during winter. There would have been no for pipes running under the floor and on the walls. Rather such installations indicate that the air in the chambers had to be heated to significantly above normal room temperature - as is the case with hot air disinfestation chambers.

In Auschwitz: Technique and Operation of the Gas Chambers, Jean-Claude Pressac quotes a "Medical Field Manual: Field Sanitation" published in 1940 by the US War Department:

173: Improvised Hot Air Disinfestors:
Clothing and equipment may be placed in ovens, boxes or cans and subjected to dry heat. Small buildings or dugouts may be converted into hot air disinfestors by installing heating apparatus which will heat the air to 150 F[ahrenheit= 71°C]. Clothing should be hung loosely and exposed about thirty minutes.[10]

Thus when Pressac wrote his sacrilegious Historama article in 1995, he was fully aware that sheds like those described in the Kozak testimony could be converted into hot air disinfestation chambers.

In addition, it might be pointed out that the presence of the Kozak ovens in the "gas chambers" would themselves have provided something of an obstacle to the killing process. First of all, they would take up some of the floor area, thus slightly lowering the capacity of each chamber; and secondly, still hot ovens would have caused panicked reactions in those victims who were pressed against them, making the filling-up of the chambers more difficult.

The alleged gassing(s) with Zyklon B

In the German manual "Directives for the use of prussic acid (Zyklon) for the destruction of vermin (disinfestation)", presented at the IMT Nuremberg as Document NI-9912, we can of the precautions necessary when using Zyklon B. Among other things, we are informed that the building space where the gassing takes place has to be carefully sealed, and that "presence of heating shafts, air shafts, breaks in the walls, etc." may hinder the gassing from being carried out at all.[11]

We also read in the same manual that "every person must at all times be able to prove that he has official authorization for the use of prussic acid." It is further stated in it that "untrained persons or persons who are trained but who do not yet hold a certificate may not be called in to work on gassing operations, nor must they be taken into gas-filled rooms." The early Bełżec staff was at this point exclusively drawn from the euthanasia program T4, where killings allegedly had been carried out using bottled carbon monoxide, not Zyklon B. There is no indication that Oberhauser or anyone else at the camp had undergone the training required for safe use of Zyklon B. One might in addition ask where the Bełżec SS got hold of the gas. It was hardly available in the local Polish market, but had to be required from the German government owned manufacturers via a rather intricate bureaucratic process.

Was the barrack described by Kozak, the alleged first phase gas chamber building, suitable for Zyklon B gassings? Orthodox Bełżec chronicler Robin O'Neil writes in his online book Belzec: Stepping Stone to Genocide

The camp operation in those early weeks was not without difficulties. The gas chamber was nothing more than a wooden barrack. To enhance this deception, the false showerheads that Fuchs had been unable to fit earlier were now installed and signs indicating a bathhouse displayed. Despite all their efforts, the construction team was unable to make the unloading doors airtight. According to Werner Dubois, on each gassing operation in the wooden barrack, sand had to be piled against the outer door to try to rectify this problem. After the gassing, the sand had to be removed to allow access to the corpses.[12]

Does it really stand to reason, that the German staff, at the risk of their own lives, would have carried out gassings with Zyklon B in a wooden shed which despite efforts could not be made airtight?

Excursus: Kozak and the Bełżec "electro-chambers"

As is perhaps well-known, propaganda reports and anonymous accounts circulated during the war and the first year of its aftermath claimed that untold thousands of Polish Jews had been killed at Bełżec in large death chambers by means electrocution. In a report delivered to the Polish government in exile in London on July 10, 1942, we read:

Once discharged, the men go into a barrack on the right, the women into one on the left, to undress, supposedly for taking a bath. Then the groups go together into a third barrack with an electric plate where the execution occurs. The bodies are then taken by means of a railway to a pit, about 30 meters deep, situated outside the fence.[13]

In the report Hinrichtungs- und Vernichtungslager Belzec from 1944, World Jewish Congress delegate Dr. Abraham Silberschein described the alleged killing process in this way:

After unloading, the men are directed to the right, the women into the barrack on the left. They were ordered to undress and to prepare for an end. They then must enter a third barrack, which contains an electric oven. The executions take place in this barrack. After that, the corpses are taken by train to a ditch beyond the barbed-wire fence.[14]

The electro-chamber story reached its apex in Stefan Szende's book Den Siste Juden Från Polen ("The Last Jew from Poland"), published in Stockholm in 1944, in which the electrocution scenario has been fused with a ridiculous account of mass incineration:

When trainloads of naked Jews arrived they were herded into a great hall capable of holding several thousand people. This hall had no windows and its flooring was of metal. Once the Jews were all inside, the floor of this hall sank like a lift into a great tank of water which lay below it until the Jews were up to their waists in water. Then a powerful electric current was sent into the metal flooring and within a few seconds all the Jews, thousands at a time, were dead.

The metal flooring then rose again and the water drained away. The corpses of the slaughtered Jews were now heaped all over the floor. A different current was then switched on and the metal flooring rapidly became red hot, so that the corpses were incinerated as in a crematorium and only ash was left.

The floor was then tipped up and the ashes slid out into prepared receptacles. The smoke of the process was carried away by great factory chimneys.[15]

It might very well be that the sight of the metal sheet covered walls and floor of the hot air disinfestation chambers inspired underground propagandists to come up with the gruesome but also patently absurd story of the Bełżec electrocution chambers.


Exterminationist writers have asserted that experimental homicidal gassings with bottled carbon monoxide and Zyklon B were carried out at the Bełżec camp during early 1942. The claim mainly rests on witness statements made by former Bełżec SS Josef Oberhauser in the early 1960s. Faced with the October 14, 1945 statement of the local Polish witness Stanislaw Kozak, which describes a shed containing three rooms with a large oven placed in each of them, some of these writers further assert that the ovens were used to heat the air of the "gas chambers" on cold days, in order to make the gassings more efficient.

As has been shown in this article however, the eyewitness testimony when scrutinized and compared to scientific knowledge as well as documentation on the use of Zyklon B, indicates a number of factors which taken together makes such experimental homicidal gassings hardly conceivable. In fact, everything points to that the installations described by Kozak were harmless components in a facility for hot air disinfestation.


Mattogno, Belzec in Propaganda, Testimonies, Archeological Research, and History , Theses & Dissertations Press, Chicago 2004, p. 45.
Mattogno, Belzec , p. 45.
Mattogno, Belzec , p. 46, note 109.
Mattogno & Graf, Concentration Camp Majdanek. A Historical and Technical Study , Theses & Dissertations Press, Chicago 2003, p. 130.
J-C Pressac, "Enquête sur les camps de la morte," in Historama , no. 34, 1995, pp. 120 ff.; quoted in Graf & Mattogno, Treblinka. Extermination Camp or Transit Camp? Theses & Dissertations Press, Chicago 2004, p. 291.
Quoted in Klee et al., The Good Old Days , Free Press, New York 1991, p. 230.
Statement by Josef Oberhauser in Munich on December 12, 1960, ZStL, Az: 208 AR-Z 252/59, referred to in Michael Tregenza, "Belzec - Das vergessene Lager des Holocaust", in: I. Wojak, P. Hayes (eds.), "Arisierung" im Nationalsozialismus, Volksgemeinschaft, Raub und Gedächtnis , Campus Verlag, Frankfurt/Main, New York 2000, pp. 248-249, 263.
Online (p. 3.)
J-C Pressac, Auschwitz: Technique and Operation of the Gas Chambers , Beate Klarsfeld Foundation, New York 1989, p. 66.
Reproduced in ibid, pp. 18-20.
Quoted in Carlo Mattogno, Belzec in Propaganda, Testimonies, Archeological Research, and History , Theses & Dissertations Press, Chicago 2004, p. 12. It may be worthy of note that the number of barracks coincide with that in the Kozak testimony, although their respective purpose differ.
Ibid, p. 16.
Quoted in ibid, pp. 18-19.

Additional information about this document
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Author(s): Thomas Kues
Title: The Alleged Experimental Gassings at Belzec
Published: 2008-09-10
First posted on CODOH: Sept. 8, 2008, 7 p.m.
Last revision:
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