First the Nazis allegedly used bottles of pure carbon monoxide in their Euthanasia institutes. From there they decided to use engine exhaust to gas Jews in their Reinhardt camps. Some say diesel exhaust, others say gasoline exhaust. As diesel exhaust can't kill in sensible periods of time, let's say they used gasoline exhaust. So when fuel was scarce because of WW2 shortages, the Nazis decided not to use gas with 100% CO (carbon monoxide) as in their Euthanasia 'gas chambers' or gas with 18-35% CO as with the wood gas generators used by Europe's civilians because of oïl shortage, but gas with 1-2% CO (http://en.wikipedia.org/wiki/Vehicle_ex ... on_engines), far less lethal.
Safety Poster No. 684 from November 1943 as shown in Der gewerbliche Kraftverkehr, Heft 11/12 1943, page 147. The text reads: “Attention–Danger of Poisoning!” In the background, it reads: “Carbon monoxide.” At the bottom, the text reads: “Start generator fire only in the open or—vent only to the open outdoors! Never refill inside a closed room!”
Later they opted for hydrogen cyanide (Zyklon B) to gas Jews at Auschwitz and Majdanek. But they didn't convert the sophisticated, safe and efficient delousing cyanide gas chambers they had to kill lice and combat typhus. No. They supposedly decided to drill holes in a roof and just pour Zyklon B pellets on the floor of an unheated room (Auschwitz Krema I), making the release of hydrogen cyanide much slower than in their delousing gas chambers.
Delousing gas chamber
A little later they decided to build new gas chambers, at Auschwitz II (Birkenau). In order to make the release of hydrogen cyanide even slower, they thought it would be a great idea to drill holes in the roof of cold underground morgues (Krema II and III).
Fortunately they had to evacuate Auschwitz and WW2 ended before they had the opportunity to build gas chambers even less efficient, or they would probably have tried to gas Jews with steam or pure oxygen.
Last words by Mr Friedrich Paul Berg:
HITLER'S GAS CHAMBERS
Just as there were no weapons of mass destruction (WMD) in Iraq prior to the recent war – no Jews or gentiles were ever killed in gas chambers or gas vans by the Nazis. The “intelligence experts” and “scholars” were wrong. Whatever crimes the Nazis and Hitler did commit, they did not include gassings of Jews or anyone else. Historians have blindly accepted the wildest, pseudo-scientific nonsense imaginable. Until a few hundred years ago, people believed in overwhelming evidence to support religious claims about witchraft and contacts with the devil -- but, it was ALL bad evidence, most of it having been manufactured in seemingly fair, legal proceedings by skilled and highly-educated fanatics. Today, we know that there were no witches ever, anywhere, and that the devil is a hoax also. The anti-German, anti-Nazi gassing claims are the exact same kind of phenomenon.
Hitler had superb, cyanide gas chambers – but they were used ONLY to keep people alive. Those gas chambers were used in many strategic locations throughout eastern Europe to fumigate entire railroad trains, for example, with cyanide gas from Zyklon-B. Other superb gas chambers were used in POW camps and concentration camps, including Auschwitz, to fumigate everything from clothing to furniture, also with cyanide gas from Zyklon-B. Those superb gas chambers certainly could have been used for mass murder as well. The great irony is that none of those real gas chambers have ever been implicated in any of the holocaust gassing claims. Instead, the Nazis supposedly used diesel exhaust and Zyklon-B–but, here is where it gets really crazy, the Zyklon-B was simply dumped, supposedly, through small holes in the roofs of cellars–without the warmed, forced air and circulation that was routinely used in all of Germany's most highly-advanced gas chambers. See my essay: http://www.nazigassings.com/zyklondelousing.html.
There is not even a valid theory as to how the alleged homicidal, mass gassings could have happened. All of the alleged gassing methods are so technically absurd that they cannot withstand any serious scientific investigation – no doubt, that is precisely why the official defenders of the holocaust hoax must imprison critics instead whenever possible as in Germany, France, Austria and elsewhere. The defenders of the so-called “holocaust” are ruthless, shameless bigots.