Zyklon B is a product that gives off hydrocyanic gas by evaporation.
It is used for the disinfestation of ships, silos and dwellings and, generally, for the elimination of pests.
It is still manufactured today in Frankfurt-on-Main and sold in Western and Eastern Europe, the United States and the rest of the world.
Hydrocyanic gas is highly poisonous, thus very dangerous. An amount equal to a thousandth of a man’s body weight is sufficient to kill him. In an enclosed space it will poison a person in several seconds, with death ensuing in several minutes. One may lose consciousness and die upon absorbing this gas through the skin.
This gas sticks to surfaces. It sticks not only to human skin and mucous membranes, to the point of permeating them, but also to wood, plaster, paint and cement, and permeates them as well. In an ordinary enclosure containing those materials, the gas cannot be ventilated immediately after use; there will have to be a natural aeration lasting nearly 24 hours.
Only trained personnel having passed a certificate course may use this product. When doing so they must wear gasmasks fitted with special filters for hydrocyanic acid.
The preparations needed for the gassing of an enclosure, for example a dwelling, are lengthy and meticulous, especially as concerns the obtaining of good airtight conditions.
The Zyklon granules from which the hydrocyanic gas is released are not tossed or scattered about at random: that would pose dangers later on. A calculated diffusion in the air must be ensured; therefore the granules are placed on paper mats spread out on the floor.
When the gas is believed to have done its job, specialised personnel enter and open the windows and doors to allow a natural aeration. This is the most critical moment: the airing-out stage presents the greatest danger for both participants and non-participants, and therefore must be carried out with particular caution, always wearing a gasmask. As a rule the crew must at all times be able to reach the open air rapidly; the gas must be evacuated in a manner excluding any risk to non-participants.
The aeration lasts a minimum of twenty hours.
At the end of that period the personnel return, still in their gasmasks. If possible, they raise the indoor temperature to 15° C. They then leave, to return after another hour, again in their gasmasks, and proceed with a test to verify the evacuation. If the results are favourable the place is declared to be accessible without need of a gasmask. But if the place is a dwelling, no-one must sleep there for the first night and the windows should remain open through that night. Mattresses, bedrolls and cushions must be beaten or shaken for at least an hour, for they will have been impregnated with gas.
Hydrocyanic gas is inflammable and explosive; there must be no naked flame in the vicinity, and smoking is positively prohibited.
More generally, in order to be able to enter premises where hydrocyanic gas is present one must always wear a gasmask with a particularly strong filter. Two hypotheses are to be considered: exposure to concentrations of less than 1 per cent in volume, and exposure to concentrations equal to or greater than 1 per cent.
In the first case, a man will be able to perform some light work; for example, he may open windows that are easy to open, but on condition that after each stage he go outside, remove his mask and breathe the open air for at least ten minutes. In the second case, exposure to the concentrations in question is to be tolerated only in the event of necessity, and then for a period not longer than one minute.
This gas can be used in pressurised fumigation chambers. It is used in the United States for the execution, in gas chambers, of criminals sentenced to death. A person need only see one of these chambers and become acquainted with the procedure for the use of hydrocyanic gas to realise how difficult and dangerous it is to utilise it for the killing of a lone individual.
During the First World War combat gasses had been used widely, but with numerous disappointments, and posing nearly as great a danger for the user’s own troops as for the enemy, so true is it that gas is the least controllable of all weapons. Many suicidal or accidental poisonings are there to prove this fact. But following the war some Americans, wishing to see a more humane method for putting condemned criminals to death, believed that nothing would be at once so humane and so easy to use as a powerful gas, putting the subject to sleep until death ensued. It was when they wanted to put their idea into practice that they realised the difficulties. The first execution by hydrocyanic gas took place in the penitentiary at Carson City, Nevada, in 1924; it narrowly missed turning into a catastrophe for all those involved. The Americans would have to wait until 1936/1938 to obtain more reliable gas chambers. But even today this method of execution remains fraught with risk for the executioners and their entourage.
The cubicle called “gas chamber” is made entirely of glass and steel in order to provide an environment in which the gas will neither stick excessively to surfaces nor penetrate them. The glass and steel are quite thick for various technical reasons, but especially that of enabling the creation of a vacuum in the chamber, with a view to ensuring suitable air-tightness. But a vacuum so created entails a danger of implosion of the enclosure concerned: therefore the structure must be very strong indeed.
Once the condemned man has died from the gas emission the real difficulties begin. It is in effect necessary for others to enter a place that, at the moment, is full of deadly gas, and to handle a corpse impregnated with that gas.
The gas is not evacuated towards a chimney leading to the outside, since that would be letting dangerous poison into the atmosphere. In fact, it is forced back into a mixer where it is neutralised by a chemical base (ammonia). The acid is thus replaced by a salt, to be washed away with a large volume of water. Nevertheless, the chamber still remains dangerous for quite some time, as does the body: the physician and his aides, who will have to enter the chamber and drag it out, must take certain necessary precautions. They will wait until a warning substance (phenolphthaline) signals that the deadly gas has been neutralised, at least for the most part. They will be wearing gasmasks with special filtering cartridges, as well as rubber gloves and aprons, and will wash the corpse very carefully with a shower jet, particularly the mouth and all folds of the body.
Beforehand, the simple preparation of the chamber for an execution will have required two days of work by two specialised men. The machinery involved is relatively substantial.
Using hydrocyanic gas to kill just one man is thus a much more complicated and dangerous matter than one might generally imagine.
Gas chambers of so complicated a nature as made necessary by the use of deadly hydrogen cyanide must not be confused with the rudimentary structures used by armies throughout the world to train recruits in the wearing of gasmasks with ordinary filter cartridges. The enclosures concerned are also called gas chambers. The gas employed will generally be not very poisonous, and easy to evacuate; the air-tightness of such enclosures is quite relative.
Knowing all this, one is quite surprised at reading the testimonies or confessions regarding the Germans’ supposed use of Zyklon B to execute not one human being at a time, but hundreds or even thousands. The most complete of these testimonies or confessions is that of the first commandant of Auschwitz, Rudolf Höss (not to be confused with Rudolf Hess, the prisoner of Spandau). Höss is said to have drafted for his Communist jailers and judges a confession the text of which was supposedly reproduced in 1958, i.e. eleven years afterwards, in the original German by Dr Martin Broszat, a member of the Institute for Contemporary History in Munich. This confession is known to the general public by the title Commandant of Auschwitz. First on page 166, then on page 126 of the German edition the reader learns the following:
A half-hour after releasing the gas, they would open the door [of the gas chamber in which the bodies of several thousand victims lay] and turn on the ventilation device. They would immediately begin taking out the bodies.
He goes on to say that this tremendous job of removing thousands of bodies, from which they also extracted the gold teeth or cut off the hair, was carried out by resigned and indifferent persons who, all that time, did not stop smoking or eating.
The description is astonishing. If those men were smoking and eating, they were obviously not wearing gasmasks. And how could they smoke in a room filled with inflammable and combustible gas vapours? How could the whole job be done near the doors of crematory ovens in which thousands of other bodies were being burnt? How could they enter a chamber still full of poison gas and handle bodies infused with that gas, immediately after the door’s opening? How could they set about such a gigantic task, for hours on end, when trained personnel, in gasmasks, can only remain in such an atmosphere for several minutes, and on condition that they only perform efforts no greater than that required to open an easily opened window? How could they, with their bare hands, extract teeth and cut hair when, after an execution in an American gas chamber, the first task of the physician who enters, in his gasmask, is to tousle the corpse’s hair with his rubber-gloved hands in order to rid it of the hydrogen cyanide molecules that remain despite all the precautions taken? Who were those beings endowed with such supernatural powers? From what world did those fabulous creatures come? Did they belong to our world, governed by inflexible laws well known to all men of physics, medicine, chemistry, toxicology? Or did they belong instead to a world of the imagination where all those laws, including the law of gravity, were overcome by magic, or made to vanish by enchantment?
If Rudolf Höss were alive today we would be able to ask him these questions. Unfortunately, after his confession to the Communists he was hanged. It remains for us, therefore, to put these questions to others who have given evidence in court saying that they saw those “gas chambers” functioning. No court has yet put questions of this type, for example, to a Dov Paisikovic or to a Filip Müller. Happily, what the judges have not done, an American historical institute did do, in Los Angeles on September 3, 1979. The Institute for Historical Review (P.O. Box 1306, Torrance, California 90505) has even promised a reward of $50,000 for anyone who can answer with suitable proof. But, after nearly a year, nobody has come forward, not even Filip Müller, who lives in West Germany (Mannheim, Hochofenstrasse 31). His book, recently published in Germany, Britain, America and France, does not offer a single element of response to these questions. Moreover, it piles up additional mysteries, rendering the affair inextricable.
30 novembre 1980
I keep at the disposal of any witness or of any court a study that ends with the following question: “What proof is there demonstrating the reality of ‘gassing’ at Auschwitz that had not already demonstrated the reality of ‘gassing’ at Dachau?”
We know today that there were never any “gassings” at Dachau, but for many years a host of proofs and testimonies were presented that purportedly demonstrated the reality of such “gassings”. It has seemed to me a good idea to refer back to the evidence and testimonies previously accepted as proof that there had been “gassings” at Ravensbrück where, likewise, it is now established that there were none. My conclusion is as follows: between, on the one hand, the documents about Dachau (or Ravensbrück) and, on the other, those about Auschwitz, there is no difference in quality but merely in quantity. As concerns those first “gas chambers” or the first “gassings”, stories were made up and circulated over a span of some 15 years, whilst as concerns the others the process has gone on for 35 years. With the former as with the latter there lack neither official documents nor details specified to the nearest centimetre.
November 30, 1980
On the subject of Zyklon B, see Nuremberg document NI-9098 and, especially, NI-9912.
On the type of gasmask required, see the US Army manual The Gas Mask, Technical Manual No. 3-205 (TM 3-205; 1-2), War Department, Washington, September 22, 1943, drafted under the direction of the Chief of the Chemical Warfare Service; U.S. Government Printing Office, 1943, 154 p. In particular, page 55.
On the testimony attributed to Rudolf Höss, see: Kommandant in Auschwitz, Autobiographische Aufzeichnungen, eingeleitet und kommentiert von Martin Broszat, Deutsche Verlagsanstalt, Stuttgart 1958.
On Filip Müller, see: Sonderbehandlung, Drei Jahre in den Krematorien und Gaskammern von Auschwitz, Deutsche Bearbeitung von Helmut Freitag, Verlag Steinhausen, Munich 1979, 287 p. English translation: Eyewitness Auschwitz, Three Years in the Gas Chambers, Literary Collaboration of Helmut Freitag, foreword by Yehuda Bauer, Stein and Day, New York 1979, 180 p. French translation: Trois ans dans une chambre à gaz d’Auschwitz: Le Témoignage de l’un des seuls rescapés des commandos spéciaux, Pygmalion/Gérard Watelet, Paris 1980, 252 p., preface by Claude Lanzman.