The room or the enclosure needs to be ‘air tight’ with gas suppression systems in order to contain the agent long enough to extinguish a fire. This requires the complete sealing of all walls, floors and ceiling slabs including doorways and openings. Full discharge test or an enclosure integrity test (also known as a door fan test) is needed as part of the system acceptance process in order to prove the system functionality. That is not the case with HI-FOG®, which fire fighting performance has been proven in number of full scale fire tests. HI-FOG® can be activated at any point in time without delay – thus increasing the safety of the facility and its personnel.