I don't think that's accurate. Dachau did have a gas chamber, but my recollection is that it was not used. Dachau was not a death camp.
However 32,000 people did die there. Just from the bad treatment etc.
Looks like I’m right and the author is giving short shrift to facts. (And, by the way, he left out the hangings).
“There is no credible evidence that the gas chamber in Barrack X was used to murder human beings.”
http://www.ushmm.org/wlc/en/article.php?ModuleId=10005214