I think the biggest issue with Halon system is the gas is very bad for the Ozone layer, hence usage is limited. In a normal server room equiped with Halon, if the gas comes down you can breath nomrally and walk outhte room and not have to seek medical assistance. The problem is it is highly effective at removing oxygen so in a small room ll oxygen could be depleted, and in a large room and you crawl on th ground then there is little oxygen. But if you walk normal, at head height there should be enough to breath fine. My fire training at Sun shwoed lots of test examples of people walking through servers rooms filled with Halon.
The newer things like FM200 with a very sophisticated release mechanism should put oiut most fires but still allow safe oxygen levels for breathing, even if you are unconscious on the ground.
The newer things like FM200 with a very sophisticated release mechanism should put oiut most fires but still allow safe oxygen levels for breathing, even if you are unconscious on the ground.