Pressac’s Solution – 'Gas Chamber' Ventilation

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Pressac’s Solution – 'Gas Chamber' Ventilation

Postby PLAYWRIGHT » 1 decade 1 year ago (Wed Apr 15, 2009 7:21 pm)

Did anybody ever notice this before? Jean-Claude Pressac – the only Holo defender I actually admire, his books are far more revisionist than acknowledged, which is probably why his sponsors turned against him – anyway, this is his solution to a problem raised by a revisionist.

Jean-Claude Pressac, Auschwitz: Technique and Operation of the Gas Chambers, Page 377


(Reply to the argument in a letter from a revisionist)

Following the exchange of letters and telephone calls with a correspondent who doubts the reality of the gas chambers, I have extracted two of his arguments that appear to me valid.

Describing the ventilation system of Leichenkeller I [of the future Krematorium II as per the cross-section on drawing 933], he pointed out to me that the air entered through the upper orifices, then was extracted through the lower ones, and concluded:

“This arrangement is perfectly suitable if the room is used as a morgue: the air entering cools, becomes denser, and is extracted from the lower part.”

He then asked me to imagine:

“the situation in the LK 1 after the gassing of a large number of people: the corpses are heaped on top of one another; they block most of the air extraction orifices; the room is full of warm toxic gas; how can there be rapid and efficient mechanical ventilation? I would say that it is nor possible...”

These remarks mean that Leichenkeller I used as a gas chamber had a poorly designed ventilation system and in the case of large-scale gassings [3000 people in 210 m² according to Nyiszli, or 13.3 per square meter], the lower orifices being blocked ventilation would become impossible [a model visible at the Museum illustrates this “maximum” case, though there are probably no more than one thousand victims depicted].

The figure of 3000 is theoretical and exaggerated, but if we take it as correct, then so is my correspondent's hypothesis and the ventilation is blocked and cannot work.

What would the SS have done in the case of such an “incident”?

They would have proceeded in two stages:

1. Open wide the doors giving basement access through the north yard and those of the undressing room, whose ventilation system working at full power would prevent the basement being contaminated:

Before putting on their gas masks, the SS would have then ordered two to four members of the Sonderkommando to put on masks, open the gas chamber door and drag bodies out into the vestibule until several of the air extraction orifices had been cleared. Then the gas-tight door would have been closed again, the ventilation restarted, and to improve its efficiency all that was required was to open the Zyklon-B introduction covers, but not until that moment. After verifying by means of a gas detector that there was no longer any danger of hydrocyanic acid intoxication outside the gas chamber, operations would have resumed their “normal” course.

2. Once the gas chamber had been emptied, a squad of fitters or bricklayers would have fixed at the end of the chamber, in the southeast corner a steel duct of about 20 cm diameter and 2 meters high or built a brick chimney of about the same dimensions connecting with or protecting one of the lower air extraction orifices and enabling it to take in warm contaminated air from above. The time taken for the “repair” would not have been longer than an afternoon. Such an incident would not have interrupted the “operation” of the Krematorium. As the documents we possess at present make no mention of such work we can assume for the moment that the case of the “3000” never occurred, the number of victims from a convoy always being less than this.

The initial ventilation system of Leichenkeller I, which was designed for a basement morgue, is not a “definitive” obstacle to using the room as a gas chamber.

To be fair, he is working with a scenario where 3,000 people are in the gas chamber, which he states never happened. The biggest day Auschwitz ever had, according to Pressac, was 9,000 people gassed and cremated in 24 hours, and he speculates that no more than 1,000 people were ever gassed at one time in either Krema II or III, the only Krema’s that had forced ventilation.

Even with only 1,000 people, the problem of blocked ventilators still comes up. Pressac’s “solution” to the problem, which nobody has ever mentioned before as he himself states, is obviously pure speculation.

Almost desperation?

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Postby Carto's Cutlass Supreme » 1 decade 1 year ago (Wed Apr 15, 2009 9:44 pm)

Hi Playwright,

Impressive post. Thankfully there's a few revisionists like you who actually read the literature.

I agree: you listen to him and suddenly there's a believer you can understand, but as you mentioned in a way he's not a believer.

I wonder who he was corresponding with.

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Re: Pressac’s Solution – Gas Chamber Ventilation

Postby Lamprecht » 1 year 2 months ago (Mon Apr 22, 2019 8:20 pm)

In order to stick to their dumb design, the Nazis even built gas chambers impossible to ventilate. Since hydrogen cyanide is lighter than air, air inputs at the top of a room and air outputs at the bottom of it would have failed to pump hydrogen cyanide out of such a "gas chamber." Such a ventilation system was the best way to keep hydrogen cyanide inside a room…or to pump cold decomposition gases (heavier than air) out of a morgue. Moreover, vents at the bottom of a room would have been often obstructed by the dead bodies of people haphazardly falling everywhere.

"Gas chamber" of Krema II & Krema III at Birkenau



Read more:

The Ventilation Systems of Crematoria II and III in Birkenau

Morgue Design: The Good, the Bad, and the Ugly
"Ventilation in an autopsy space should always be supplied high (ceiling) and returned low (floor level). This allows for the flow of air to move from top to bottom of a room, a plunger effect, and move difficult or putrid odors down and out of the room, bringing clean air past the noses of those working at the table. Return air grilles should never be located at the ceiling level as this churns the air and makes it difficult to remove malodorous smells."
"There is a principal which is a bar against all information, which is proof against all arguments, and which cannot fail to keep a man in everlasting ignorance -- that principal is contempt prior to investigation."
-- Herbert Spencer

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Re: Pressac’s Solution – Gas Chamber Ventilation

Postby Lamprecht » 9 months 5 days ago (Mon Sep 30, 2019 10:17 pm)

Pon has brought up Pressac's weak arguments regarding Gas Chamber ventilation, here: viewtopic.php?t=12751

Germar Rudolf debunks Pressac's so-called "Criminal traces" regarding the alleged homicidal gas chamber ventilation systems:
Auschwitz: Technique and Operation of the Gas Chambers—An Introduction and Update to Jean-Claude Pressac’s Magnum Opus
The Ventilation Systems of Crematoria II & III

While Pressac documents with plenty of material how the ventilation systems were installed and which motors the various fans had (see pages 370-374), this yields little information regarding the capacities of these systems, and how many air exchanges they could achieve for the rooms they ventilated.

He remedied that situation in his second book, where he documented the capacity of the fans used to ventilate each room (1993, p. 30):

- intake fan no. 450 (mm fan diameter) for Morgue #1, 4,800 m 3 /h at 40 mm water column;
- extraction fan no. 450 for Morgue #1, as above;
- extraction fan no. 550 for Morgue #2, 10,000 m 3 /h at 55 mm water column;
- extraction fan no. 550 for furnace room, 10,000 m 3 /h at 32 mm water column;
- extraction fan no. 375 for autopsy room, 3,000 m 3 /h at 20 mm water column.

Using each rooms volume, Pressac even gives the number of air exchanges per hour:

- (4,800 m 3 /hn-483 m 3 ) = 9.94 exchanges for Morgue #1;
- (10,000 m 3 /hn-966 m 3 ) = 10.35 exchanges for Morgue #2;
- (10,000 m 3 /h-H,031 m 3 ) = 9.70 exchanges for the furnace room;
- (3,000 m 3 /hn-300 m 3 ) = 10 exchanges for the autopsy room.

The original plan created for a new crematorium at the Main Camp provided for the following fan motors for each room (see Illustration 56a&b): 141

- 1 HP for fan no. 375, autopsy room.
- 2 HP for both fans no. 450, Morgue #1
- 3.5 HP for fan no. 550, furnace room
- 5.5 HP for fan no. 550, Morgue #2

The difference in motor power between the furnace room (3.5 HP) and Morgue #2 (5.5 HP), although they both have the same fan with the same capacity, results from the higher friction expected in their respective ducts, indicated by the higher pressure difference of Morgue #2 compared to that of the furnace room (55 mm as against 32 mm water column).

In early 1942, the power of all motors was increased, while the fan types remained the same, meaning that the air friction of the respective air ducts had been underestimated. To maintain the planned capacity, stronger motors had to be provided. When discussing the issue of the wooden fan casing, we already encountered the motors planned for the morgues: two 3.5 HP motors for Morgue #1, and a 7.5 HP motor for Morgue #2. From the Topf blueprint D 59366 of March 10, 1942, 142 we can glean these powers, plus the one for the furnace room (4.5 HP), and the autopsy room (1.5 HP). That upgrade in motor power happened at a time when no criminal redesigning of these buildings is said to have happened yet. This is supported by the fact that all rooms obtained stronger engines, not just the one room where we would expect an upgrade to handle toxic gases: Morgue #1.

Interestingly, when looking at the planned fan capacities, Morgue #1 had a slightly smaller capacity than Morgue #2 (the undressing room) and the autopsy room, even though it is safe to assume that the planning engineers were aiming at installing roughly the same capacities for the entire building. That didn’t change when the motor power upgrades were made.

In his 1993 book, Pressac commits a blunder by calculating a presumed new capacity of the fans by dividing the old capacity by the old motor s power and multiplying it by the new motor s power, then rounding the result generously (pages 74 and 118). This is arrant nonsense. These motors had a higher power, but they did not spin faster, and the fans they drove were still the same as before. These stronger motors simply could maintain the same rpms even at higher loads. But since the fans were not changed, their nominal capacity did not change either. 143

The ventilation capacities themselves indicate what these rooms were meant to be. According to Heepkes book on the design of crematoria, morgues should be equipped with a ventilation capacity of at least 5 air exchanges per hour and should reach 10 air exchanges in cases of intensive use, 144 which certainly was what the Auschwitz crematoria were facing. Expert literature on fumigation chambers, on the other hand, recommended 72 air exchanges per hour. 145 “Responsibly” planned homicidal gas chambers would have had a ventilation capacity at least close to that of professional fumigation chambers.

No upgrade to the ventilation system of Morgue #1 happened in late 1942 or early 1943, when this room is said to have been assigned its new role of chemical mass slaughter. Hence, there is not only no criminal trace here, but quite to the contrary.

When addressing the “blue-wall phenomenon,” I mentioned that Pressacs claim of brief ventilation times for the hypothesized mass gassings is flawed. This statement is not only based on the fact that the blowers installed were designed for morgues, but also on a number of issues overlooked or ignored by Pressac: 146

1. Any ventilation could have been successful only after Zyklon B had released its fumes almost completely, which would have taken an hour and more.

2. Even for an empty room, a complete air exchange does not equate the complete replacement of “old” air by fresh air. If old and fresh air mix thoroughly, only some 63% of old air gets removed with every air exchange.

3. A thousand or more corpses lying on the floor would have created many air pockets where almost no air exchange would have occurred, delaying a successful ventilation for hours.

4. The air exhaust openings near the floor would have been partially blocked by dead inmates, reducing the systems performance.

5. The air intake and exhaust openings on the same wall were only some 2 m apart from another, while the opposite wall was 7 m away. Hence, the system tended to produce an air “short circuit,” where fresh air blown in gets sucked out right where it entered, rather then mixing with the rooms air.

For these reasons, successfully ventilating Morgue #1 would have taken hours.
"There is a principal which is a bar against all information, which is proof against all arguments, and which cannot fail to keep a man in everlasting ignorance -- that principal is contempt prior to investigation."
-- Herbert Spencer

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Re: Pressac’s Solution – 'Gas Chamber' Ventilation

Postby Lamprecht » 8 months 1 week ago (Wed Oct 23, 2019 9:59 pm)

- The main alleged homicidal gas chambers of Auschwitz (Kremas II and III) were equipped with ventilation systems. This is often claimed to be evidence that they were homicidal gas chambers

- Actually, the blueprints of the rooms claim that they are morgues, and the ventilation system capacities strongly suggest this use.

- Documents recovered from the camp show that the so-called "Homicidal gas chambers" had a lower ventilation capacity (measured by air exchanges per hour) than the alleged "undressing rooms". Other rooms had an even greater capacity besides the delousing chambers which had by far the greatest

- The ventilation shafts at the bottom of the room, rather than at the top, would have made ventilation impossible with all of the gassed corpses present. Such ventilation designs are useful for a morgue, not a homicidal gas chamber (see my first post for more info)

- Various other structural flaws made the ventilation systems inefficient in general (discussed more in-depth in my most recent post above)


From Germar Rudolf: Ventilation Systems

Fact: All rooms in Crematoria II and III were equipped with efficient ventilation installations.[137]

Incorrect conclusion: Morgues #1 of Crematoria II and III were converted into homicidal “gas chambers” equipped with installations for the intended purpose of extracting poison gases.[138]

Correct conclusion: It is in fact inconceivable that a large morgue without windows and with only one door filled with innumerable bodies of the victims of epidemic disease would not be equipped with a ventilation system. The capacity of the ventilation system, however, proves that these installations were designed for typical morgues.[139] The capacity of the blowers can be gleaned from invoices sent to the Central Construction Office by the Topf corporation after installation of the systems.[140] According to this, both Morgues #1, i.e., the alleged “gas chambers” (in the invoice designated as the “B-room”), were each equipped with a 4,800 m3/hr intake and exhaust blower,[141] while for the “L-room” (the so-called “undressing room”) only one exhaust blower was installed with a flow rate of 10,000 m3/hr.[142]

When considering the volume of the two morgues (Morgue #1: 504 m3; Morgue #2: 900 m3), this results in (4,800÷504 =) approximately 9.5 air exchanges per hour for the alleged, planned “gas chambers,” and in (10,000÷ 900 =) approximately 11 air exchanges per hour for the undressing rooms. How come the SS assumed that the “gas chambers” would need less ventilation than the undressing rooms, or even less than the dissecting rooms, laying-out rooms and wash rooms, which had an even greater capacity of approximately 131/3 air exchanges per hour?

Wilhelm Heepke’s classic work on the construction of crematoria states that a morgue requires a minimum of 5 air exchanges per hour and 10 during intensive use (1905, p. 104). Thus it is clear that the ventilation installations provided for the morgues were designed, in terms of orders of magnitude, for morgues in intensive use or for morgues containing the bodies of epidemic-disease victims.

For comparison: professionally designed Zyklon-B-disinfestation chambers with circulating-air systems were equipped with 72 air exchanges per hour (Peters/Wüstinger 1940, p. 195). Furthermore, it should be mentioned that the original plans for a new crematorium in the Main Camp from 1941 – a time when even Pressac admits that the SS had no criminal intentions – provided for 17(!) air exchanges per hour for the dissecting room(!) and the morgues (Pressac 1993, p. 18). This exchange rate is considerably higher than what was later installed for all rooms of the redesigned Crematoria II and III, including the alleged “gas chambers.” Thus, on the way from beneficial planning to allegedly sinister redesign, the air-exchange rates – including that for the claimed homicidal gas chamber – had been drastically reduced (probably in order to reduce costs). This is thus the final refutation of any argument on the alleged criminal characteristics of the ventilation installations in these crematoria.

[137] The ventilation ducts of Morgue #1 are visible in the plans published by Pressac 1989, pp. 224, 289; chapter on the ventilation installations of Crematoria II and III: pp. 355ff.; engine power of the ventilation installations for all rooms in Crematoria II and III: p. 374 and 377; size of the ventilation outlets: p. 234; photo of an outlet cover in the ventilation outlets: p. 233.

[138] For Pressac see previous footnote; similar van Pelt 1999, p. 208; Gray 2000, §7.62.

[139] See in this regard Mattogno 2016h, pp. 173-176.

[140] Invoice no. 729 dated May 27, 1943. APMO, D-Z/Bau, nr. inw. 1967, pp. 246f.; ibid., 231f.: invoice no. 171 dated 22. February 1943 for Crematorium II.

[141] The engines’ power, originally set for 2 HP in a November 1941 estimate when the building’s exact specifications had not yet been fully defined, was increased in March 1942 to 3.5 HP – at a time when no criminal intentions can be imputed. The innocuous nature of this power increase is confirmed by the fact that the engine powers were increased proportionally for all the other rooms as well. Since the fan types and thus the flow rates remained unchanged, this change was caused by a more-accurate estimate of the system’s internal friction. This means that the initially calculated back-pressure of 40 mm water column was too low. Incremental calculations for estimating the ventilation-shaft resistances in Crematoria II & III according to engineering handbooks, as performed by Dipl.-Ing. Winfried Zwerenz and me in 1990, have shown that the back pressure to be expected would probably have been higher (in the region of 50-60 mm water column), due, particularly, to the primitive lids with many small holes covering the fresh-air-intake openings. See also Mattogno 2016i.

[142] J.-C. Pressac gives the output of these blowers at 8,000 m3/hr, but without proving it (together with Robert van Pelt in: Gutman/Berenbaum 1994, pp. 210, 232). He probably erroneously and impermissibly increased the fan’s flow rate proportionally to the increased engine power. See the previous note.
The Chemistry of Auschwitz—The Technology and Toxicology of Zyklon B and the Gas Chambers – A Crime-Scene Investigation

Germar continues in another section in the same work: Speed of Ventilation of the “Gas Chambers”
As shown above, when fresh air and stale air mix together, the concentration of the latter falls to only approximately 37% of the initial value after one complete air exchange, and to approximately 14% after a second exchange.

Data are only available on the ventilation installations in Crematoria II and III, so that at this point we have to ignore all other “gas chambers” in this regard. In Paragraph, the ventilation capacity of Morgues #1 of Crematoria II and III was shown to have been 4,800 m3 per hour. With a volume of free air in Morgue #1 of 440 m3, the volume of the room would be exchanged once in approximately 5-6 minutes.

For Morgues #1 of Crematoria II and III under consideration at this point, however, a further problem arises. In particular, the ventilation intake was installed only approximately 2 m away from the ventilation outlet in the same(!) wall. The distance to the ventilation outlet on the opposite wall, however, is 7.3 m, i.e., 3.5 times as far. The result, in these cellars, is a “ventilation short circuit,” especially if we assume that the victims of the alleged mass extermination were all piled up together, especially in the middle of the room, which would further lengthen the fresh-air pathway from one side of the cellar to the other. The air blown into the ventilation intake openings would therefore, for the most part, be immediately sucked out through the ventilation outlet openings located nearby.[346] Therefore, it must be expected that the actual ventilation time would be considerably increased in comparison to a perfect mixing of fresh air and stale air as a result of this poor design.

Chart 20: Simulation of the concentration of hydrogen cyanide with time in a hypothetical homicidal gas chamber of the type of Morgue #1 of Crematorium II in Auschwitz-Birkenau; see text.

In addition, if we assume that no wire-mesh introduction columns existed, as has to be assumed on the one hand based on all extant material evidence, and on the other hand because the claimed execution times could not have been achieved with it, the following problem would also arise: the Zyklon-B granules, which in the meantime would certainly have become moist, would lie trapped underneath the bodies in at least some places.
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Re: Pressac’s Solution – 'Gas Chamber' Ventilation

Postby HMSendeavour » 8 months 1 week ago (Thu Oct 24, 2019 2:31 pm)

PLAYWRIGHT wrote:Did anybody ever notice this before? Jean-Claude Pressac – the only Holo defender I actually admire, his books are far more revisionist than acknowledged, which is probably why his sponsors turned against him

Turned against him and yet they still hold his research as their entire foundation. Where did they turn against him?
Now what does it mean for the independent expert witness Van Pelt? In his eyes he had two possibilities. Either to confirm the Holocaust story, or to go insane. - Germar Rudolf, 13th IHR Conference

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Re: Pressac’s Solution – 'Gas Chamber' Ventilation

Postby Lamprecht » 8 months 1 week ago (Thu Oct 24, 2019 6:34 pm)

HMSendeavour wrote:
PLAYWRIGHT wrote:Did anybody ever notice this before? Jean-Claude Pressac – the only Holo defender I actually admire, his books are far more revisionist than acknowledged, which is probably why his sponsors turned against him

Turned against him and yet they still hold his research as their entire foundation. Where did they turn against him?
See discussions:

Was Pressac undercover?

Pressac was a closet revisionist

Jean-Claude Pressac and Revisionism

Ten Years Ago, Jean-Claude Pressac's Capitulation

And an especially good read, and a quoted portion that should answer your question:
My Memories of Jean-Claude Pressac
His bitterness might also have been increased be the fact that his second book shattered the foundations of the official Auschwitz image even more than did his first book, so that the Guardians of the 'Holocaust' Grail finally stated turning against Pressac. After the initial praise accompanying the launch of his book had subsided, Pressac was more and more ostracized. He was no longer a valuable goldmine to the guardians of the 'Holocaust' orthodoxy, but had turned into a more and more rebellious and uncontrollable Goy, jeopardizing the official historiography with each new publication. An Italian Shoa-Pharisee called him "reductionist", which reminds us in a fatal way at the term "negationist" used for all revisionists scholars by the most imbecile under the polemicists. Thus, Pressac had been banned to the purgatory of historiography, located somewhere in the middle between the revisionist hell and the 'Holocaust' paradise.

For this reason, the position as the "world's leading Auschwitz expert," until then occupied by Pressac, was taken by a trustworthy Yehudi, who was to take Pressac's theses - cleaned from all revisionist waste - and embed them into an unalterable, definitive version of Auschwitz.

The new rising star on the Holocaust firmament was Robert Jan van Pelt, a scholar who is clearly inferior to Pressac both intellectually as well as regarding his critical attitude, but who brings with him the prerequisites necessary to play the role assigned to him. I remember my disappointment and even anger after I had read the book Auschwitz 1270 to the present, which was authored by him and Deborah Dwork.[12] Van Pelt was so brazen as to repeat Pressac's essential arguments as if he had invented them, and reproduce the plans as if he himself had discovered them. Beyond that, he mentions Pressac only once in his 403 pages book (on page 304), and then only in a totally irrelevant context!

The last link is part of this series:

From Faurisson's "The Victories of Revisionism":
18) In 2000, at the end of her book Histoire du négationnisme en France (Paris, Seuil), Valérie Igounet published a long text by Jean-Claude Pressac at the end of which the latter, who had been one of the revisionists’ most determined opponents, signed a veritable act of surrender. In effect, taking up the words of professor Michel de Boüard, he stated that the dossier on the concentration camp system was “rotten”, and irremediably so. He wrote asking: “Can things be put back on an even keel?” and answered: “It is too late”. He added: “The current form, albeit triumphant, of the presentation of the camp universe is doomed”. He finished by surmising that everything that had been invented around sufferings all too real was bound “for the rubbish bins of history” (p. 651-652). In 1993-1994 that protégé of the French Jew Serge Klarsfeld and the American rabbi Michael Berenbaum, “Project Director” at the Holocaust Memorial Museum in Washington, had been acclaimed worldwide as an extraordinary researcher who, in his book on Les Crématoires d’Auschwitz, la machinerie du meurtre de masse (Paris, CNRS éditions, 1993; English title:The Auschwitz Crematories. The Machinery of Mass Murder), had, it appeared, felled the hydra of revisionism. Here, in V. Igounet’s book, he was seen signing his act of surrender.

Remark: The greater public are kept in ignorance of a major fact: the man who had supposedly saved the day for History, who once was presented by the world press as an extraordinary researcher who had at last discovered the scientific proof of the Nazi gas chambers’ existence, ended up acknowledging his error. A few years later not a single newspaper or magazine announced his death.
"There is a principal which is a bar against all information, which is proof against all arguments, and which cannot fail to keep a man in everlasting ignorance -- that principal is contempt prior to investigation."
-- Herbert Spencer

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