(the part about sim. to Cocoanut Grove refers to “only one exit”; the bit about “club owner had back exits locked” was Cocoanut Grove. Not sure about situation in Brazil. The Station fire had people panicking and using the same exit, mostly. Video of the Station fire shows how fast it spread but I think I read somewhere that they had about 2.5 to 3 minutes to get out of there, most likely via multiple exits—we’re talking 400 patrons though, but maybe after the first minute or so there was a big jam of panicked concertgoers and they got trampled a la the Who’s Cincy show...)
People were supposedly stacked up at the doors because once the doors were pinned shut with all of the people pushing to get out, the doors could not be pulled opened.
Mass State Law (not sure if it has been done by the Feds) building codes now state that all buildings such as these need to have all exit doors opening out.