Have you ever gone into a building somewhere and never saw an exit sign? Did you see a pull easily visible for the fire alarm? If you have been to buildings like this and did not see these required things, chances are they are not following fire codes for their area. All buildings are supposed to have their exits marked clearly for everyone to see. There should be smoke alarms visible somewhere and even a fire extinguisher that people could get to easily. All of these things are just common sense whether they are all included in a local fire code or not.
In many places buildings are required to have sprinkler systems installed, especially if the building has more than a couple of floors. These sprinklers are there to ensure that they will go off and start wetting everything down at the first hint of smoke or fire. Sprinkler systems inside of buildings have probably kept many fires from getting out of control and burning the building to the ground. When the sprinklers go off, you will know that chances are good that there is a fire going on even if the fire alarm has not yet sounded.
Building codes are there for one reason and that is to make sure that it is safe for people to inhabit or visit. This is why there are always signs displayed at exits. During a fire many times people panic and might not be able to find their way out. Exit signs that are brightly lit and easily visible have saved many lives. Sometimes a building code will only allow a certain number of people in the building at one time. This is because there might not be enough exits for more than the specified number of people to escape easily in the event of a fire or other disaster like a flood or earthquake.
The overcrowding of a building has resulted in deaths many times in the past. Some of the best examples have been nightclubs that were overflowing with people. When the fire broke out, people were literally trampled to death trying to escape. Many of them could not escape and were burned alive or trapped in the building as a fire caused it to collapse.
Some business owners will try to get around safety codes because it costs a lot of money sometimes to meet these codes. If they would only think of the lives they could cause to be lost by not adhering to the codes, they probably would not hesitate because of the costs. Many business owners have been sued later by families who lost loved ones in buildings that burned that did not meet safety code requirements.