I've been working in the fire alarm/life safety industry for 30 years. From what I've read so far most if not all of the deaths were due to smoke inhalation. It would appear that the doors to the unit where the fire started did not automatically close. I don't claim to know all the codes and standards across the US but I would be very surprised if automatic door closers weren't a requirement on the exterior doors at the units. Likely broken or improperly maintained. Considering the construction would have required firewalls all the way around the units had the door closers been in place and functioned properly likely no one would have died. At least that's based on what I've heard so far. Absolutely terrible and preventable.
