The profession of firefighter is one of the most risky professions. Firefighters are not only people who put out fires, they save people and animals and deal with other various interventions. Every day or every shift is different and they can never know when and for wath type of intervention a report will come. First of all, it is necessary to understand how and under what conditions burning can occur. Firefighters can encounter many problems and dangers during interventions in closed spaces, among them are the occurrences of flame shocks such as Flashover and Backdraft, which often result in fatal consequences for firefighters and can also cause great material damage. It is very important that they are familiar with their signs in order to be able to recognize them on time and protect themselves from them or, if possible, prevent them. In order to greatly reduce the casualties of firefighters, firefighter training began in flame shock simulators because the conditions in such simulators were close to real situations during interventions in closed spaces fires. The training is conducted in safe conditions, theoretically, where you learn how to behave in the flame impingement simulator, how to move in it and work with the nozzle blocking the flame impingement. It is very important that the firefighters are in good condition and that they know how to choose the correct extinguishing tactics for each intervention. Instructors also play a very important role when training firefighters in the flame shock simulator. They are there to impart theoretical knowledge to the firefighters and to do it all in safe conditions for both them and themselves.