Some passages in the building, including emergency exits were blocked, making it difficult for people to escape and fire brigade personnel to rush in. Moreover, there were also several inbuilt modifications.
The mandatory requirement of leaving a six metre gap for drive in during emergencies was also not in place, a senior fire brigade official said.
Storing 10 barrels of diesel on the terrace for use in generators was one of the most blatant violations, as also failure to maintain the fire fighting system, he said.
Several more lives would have been lost had the blaze not been extinguished before it reached the diesel, they said.
Though the building had a fire fighting system, it was not well maintained. The overhead tanks did not have water and the sprinklers were not working, he said.
The sources said rescue efforts were hampered by the huge traffic jam surrounding the area,preventing them from bringing in the 121 foot turnaround table, which could reach the 13th floor and the hydraulic platform.
The fire official said that some passages and staircases in the Carlton Towers were filled with some kind of obstructing material, preventing faster evacuation of people.
"Moreover, thronging crowds also created hurdles in rescue work. They upset all our operations", he said.
Some people jumped without following fire force instructions even before the safety mat could be arranged, he said.
Lack of knowledge on how to escape during a fire and basic safety measures by inmates only compounded the problem, he added.