Hartheim Castle Gas Chamber

The Second Leuchter Report
Fred Leuchter & Robert Faurisson


In March of this year (1989), I was asked by Mr. Ernst Zündel of Toronto, Canada, to investigate three (3) alleged execution gas chambers and crematoria in Germany and Austria. These locations, allegedly operated by the Germans in World War II, were Dachau, in Germany, and Mauthausen and Hartheim Castle, both near Linz, Austria.

The findings of these investigations and forensic analyses at Dachau, Mauthausen and Hartheim were to result in an engineering report and forensic study on the efficacy of these aforementioned facilities to function as execution gas chambers. Although these facilities seem now accepted by many established historians to have never functioned as execution gas chambers, Mr. Zündel wanted to dispel any future doubts and scientifically prove beyond any question whether these facilities were or were not used, and if they could ever have been utilized, as gas execution facilities. Resultant to Mr. Zündel's direction, I undertook this scientific investigation and evaluation. On Sunday, April 9th of this year, I arrived at Dachau with the following team: Carolyn Leuchter as secretary/technician; Dr. Robert Faurisson, advisor and consultant; Mark Weber, historian and author of contemporary European history; Tijuda Rudolf, interpreter; Steven Devine, technician; Eugen Ernst, cinematographer, and Kenneth Ernst, assistant cinematographer. The following day, Monday, April 10th, we inspected Mauthausen and Hartheim Castle, near Linz, Austria. This report and my findings are resultant to these investigations conducted at Dachau, Mauthausen and Hartheim.


The purpose of this report, and the investigations antecedent to it, is to determine whether the alleged gas chambers at three (3) specific locations, one (1) in Germany and two (2) in Austria, specifically, Dachau, Mauthausen and Hartheim Castle, respectively, could have operated in any manner resulting in single or multiple gas executions. Although cognizant of the fact that many established historians presently seem to concur that none of these installations ever functioned as a gas execution facility, the author is also aware that immediately after American capture of these locations during World War II a mass gas execution function was ascribed to these facilities, an assertion which was widely published in the international mass media at the time. It is to eliminate any further doubt or question that this investigation was undertaken and this report written.

The purpose includes the investigation and on-site inspection of physical facilities, design of these facilities and a description of the alleged gassing procedures utilized at the alleged executions. The purpose also includes estimates of the maximum number of inclusions (persons) who could possibly have fit into these alleged gas chambers and estimated venting times. This purpose does not include a determination of any numbers of persons who died or were killed by means other than gassing, or as to whether an actual "Holocaust" occurred. It, further, is not the intent of this author to redefine "Holocaust" in historical terms, but simply to supply scientific evidence and information obtained at the actual sites and to render an opinion based on all available scientific, engineering and quantitative data as to the purpose and usages of the alleged execution gas chambers and crematory facilities at the investigated locations.


The principal investigator and author of this report is an engineer and a specialist on design and fabrication of execution hardware and specifically has worked on and designed hardware in the United States used in the execution of condemned persons and by means of hydrogen cyanide gas ("Zyklon B" gas).

The investigator has inspected the alleged execution gas chambers in Poland and is the author of the report on these facilities: An Engineering Report on the Alleged Execution Gas Chambers at Auschwitz, Birkenau and Majdanek, Poland (1988), Samisdat Publishers Ltd. The author has been recognized by a Canadian court as an expert on gas chamber technology, and has testified as to the non-existence of execution gas chamber facilities at these sites.

The investigator has inspected the facilities at Dachau, in Germany, and Mauthausen and Hartheim Castle, in Austria, made measurements and taken forensic samples. Further, he purchased official printed brochures published and offered publicly for sale at the three (3) museum sites and reviewed this literature. He also reviewed the procedural literature on delousing with hydrogen cyanide ("Zyklon B") gas.


The scope of this report includes a physical inspection and quantitative data obtained at Dachau, Mauthausen and Hartheim, literature obtained at the three (3) museum sites, and a consideration of forensic samples taken at Mauthausen. For reasons explained below, no samples were removed from Dachau or Hartheim. Further, data on the design of U.S. gas chambers and the operational protocol utilized in gas executions in the United States coming from the investigator's own personal knowledge and experience in the field, as well as knowledge gained in the investigation of the alleged Polish gas chambers, were utilized in the production of this report. Additionally, operational procedure and equipment utilized at delousing facilities were considered. Utilizing all of the above data, the investigator has limited the focus of this study to a determination of the capability of the alleged gas chambers in question at Dachau, Mauthausen and Hartheim Castle to accomplish the mass murder (extermination) of human beings by the use of "Zyklon B" (hydrogen cyanide) gas.

Synopsis and Findings

After a study of available literature, examination and evaluation of the existing facilities at Dachau, Mauthausen and Hartheim Castle, with expert knowledge of the essential design criteria for gas chamber operation and the expert knowledge gained in the production of the previous study on the alleged gas chambers in Poland, the author finds no evidence that any of these installations, i.e., Dachau, Mauthausen or Hartheim Castle, frequently alleged to have been gas execution facilities, was ever utilized as such, and further finds, that because of the design and fabrication of these installations, they could not ever have been utilized as execution gas chambers.


The procedures involved in the study and forensic analysis which resulted in this report were as follows:

1. A general background study of available material.
2. An on-site inspection and forensic examination of the facilities in question, which included the taking of physical data (measurements and construction information), and a considered removal of physical samples (tile and mortar) which were returned to the United States for chemical analysis.
3. A consideration of recorded and visual (on-site) logistic data.
4. Data acquired on the previous study of the alleged gas chambers in Auschwitz I, Birkenau and Majdanek, Poland.
5. A compilation of the acquired data.
6. An analysis of the acquired information and comparison of this information with recognized and proven design, procedural and logistic information and the requirements for the design, fabrication and operation of actual gas chambers currently in use in the United States.
7. A consideration of the chemical analysis of the materials acquired on-site.
8. Conclusions based on the acquired evidence.


The Leuchter Report, which formed the basis of the author's expert testimony at the trial of Ernst Zündel, Toronto, Ontario, given on April 20, 1988, is a study of the existing alleged gassing facilities in Auschwitz, Birkenau and Majdanek, Poland. This report contains the definitive data for gas chamber application purposes for hydrogen cyanide, "Zyklon B." fumigation design and procedures, execution gas chamber design and protocol, U.S. gas chambers, medical and toxic effects of hydrogen cyanide, a brief history of the alleged German gas chambers with an emphasis on design characteristics, and a consideration of crematory technology, including a discussion of maximum cremation rates. Additionally, there is a discussion of forensic considerations of cyano-compounds and crematories.

The materials contained in the above paragraphs of the Leuchter Report (1988) are a necessary complement to this report.

The Sites: Dachau, Mauthausen and Hartheim Castle

These sites are considered separately and together, in that Dachau and Mauthausen have been at times described as camps which supplied prisoners to the Hartheim Castle site where they were allegedly executed.





Hartheim Castle

This facility consists of a masonry room adjacent to a tower of a centuries old castle. This castle was donated by the monarchy to the mental health service of Austria and was also placed under the control of the German Government when it acquired control of the Austrian Government and the mental health service. The facilty had been utilized as a mental hospital and under German control it continued as such. Allegedly, mass gas executions were conducted at this location on prisoners transferred from Dachau and Mauthausen for this purpose.

The alleged gas chamber was a lower level room adjacent to one of the castle towers. This room has an area of 192 square feet and a volume of 1,728 cubic feet. It has a vaulted ceiling of some 8.9 feet at the highest point. The installation had one (1) door and one (1) window, although a rectangular aperture has now been made into an adjacent room. There are no facilities to inlet "Zyklon B" or evacuate the gas after use. The room now has been completely remodeled. It has recently plastered walls and ceiling. There are three (3) new floor surfaces, one on top of the other. Even the door has been changed to a modern conventional mental institution cell door with a shuttered view port. The window is alleged to have been original, but would leak gas if used for this purpose. Neither the door nor the window has any provision for gasketing. Allegedly, all gassing apparatus was removed by January, 1945. In truth, there was no gassing equipment in that the walls are very thick, as characteristic of castle architecture and construction, and not easily cut to accommodate the installation of gas vents or gas inlet ports. It and the adjacent room contain memorial plaques to those who allegedly died in gassings here. The castle is presently used as an apartment building.

It appears by construction that this facility would not lend itself for use as a gas execution installation, the walls being too thick for the installation of gassing equipment. Certainly, because of the construction, any changes would be visible, and not easy to conceal. There is no provision for a gas stack for evacuation of the gas-air mixture and no way to install one. The window would certainly leak, allowing large volumes of deadly gas to escape. No samples were taken at this location because of the extensive remodelling to the facility which decidedly would obscure any test results.

For the record, the alleged gas chamber would have held only some 24 persons, utilizing the nine (9) square foot rule. Without an exhaust system this room would require at least one week to vent (refer to Dachau).

Resultant to an in-depth investigation of this installation, this investigator categorically states that in his best engineering opinion this facility was not ever utilized for, and could never have supported, gas executions. The actual use of this room in unknown to the investigator. Based on a comparison with its mirror image on the other side of the facility, it could have been a store room.

There are no crematoria extant at this locaiton.

It is perplexing to note that the official museum literature states that Dachau and Mauthausen, both having facilities equal to, or better than those at Hartheim Castle, sent inmates to Hartheim for gassing. It is unclear why this should occur since Hartheim's alleged facility would have been so difficult to construct, was so small and so distant from Dachau (200km). Based on all the available evidence it becomes abundantly clear that no gassing facilities ever existed at any of these locations.

Specialized Hardware: Non-existence

In all the author's investigations in Poland, Germany and Austria, hardware or constuction remarkable to gas chambers has never been found. There are no stacks of the necessary height, no ventilators, no gas generators, no intake air preheaters, no special paint or sealants on walls, floors or ceilings, no safety devices for the operators, and no coherent design consistently utilized throughout the alleged gas chambers. It is inconceivable that the Germans, having the highly developed technology utilized on the delousing chambers, would never have applied this technology to the alleged execution gas chambers.


After reviewing all the material and inspecting all of the sites at Dachau, Mauthausen and Hartheim Castle, this investigator has determined that there were no gas execution chambers at any of these locations. It is the best engineering opinion of this investigator that the alleged gas chambers at the above inspected sites could not have then been, or now be, utilized or seriously considered to function as execution gas chambers.

Prepared this 15th day of June, 1989, at Malden, Massachusetts.

- Fred A. Leuchter Associates, Inc.
Fred A. Leuchter, Jr.
Chief Engineer