How safe is Halon?
Halons are low-toxicity, chemically stable compounds that have been used for fire and explosion protection from early in the last century. Halon has proven to be an extremely effective fire suppressant. Halon is clean (i.e., leaves no residue) and is remarkably safe for human exposure. Halon is a highly effective agent for firefighting in closed passenger carrying areas. Due to its effectiveness and relatively low toxicity, the FAA continues to recommend or require Halon extinguishers for use on commercial aircraft
What is Halon? How does Halon Work? Is Halon legal? Is Halon Safe?
Telecom I used to work in had this installed. We were told to leave in an orderly fashion if activated. CO 2 had to be de-activated before entering.iirc