Was just about to post this re: fire doors, compartmentalisation etc...
Something has gone horrifically wrong to result in the ferocity and spread of this fire. In my mind, there is no way regulations could have been adhered to.
Something hasnt gone horribly wrong, something already was horribly wrong. An accident waiting to happen, and eventually it did.
What usually happens, is that the fire brigade has to provide a license for a building to become inhabitable. What they normally do, if they inspect a building, is give an improvement notice, when they see things are not done right, this usually means you have a certain amount of time to implement the changes they recommend, or they shut the building down.
Where it goes wrong, is in old buildings that werent built to modern fire regulations, its either impossible to upgrade them to standard, or very difficult, so the improvement notice has a very long time frame on it, in that time something disastrous could happen.
The other serious issue, is when the fire brigade issue an improvement notice rather than a prohibition notice (shut the building down immediately) when there is a serious fire risk, because there are hundreds of council residents who will become homeless overnight and under council pressure they can not just shut the building.
This is based on experience.