The big environmental issue with Halon is that its release is really bad for the ozone layer which is why it has been outlawed. It is an excellent fire suppressant but does create poisonous phosgene gas when it is exposed to the high heat of a fire. Outdoors it is not a big deal but indoors it can be deadly. The biggest issue with Halon is the cost. Because only recycled halon is available (for only a few more years until it is fully banned) re-filling a halon bottle is many hundreds of dollars. The environmentally friendly alternative is Halotron which is widely available. Halotron is a brilliant marketing name fooling most people into thinking they are getting Halon when in fact they are getting a product that is 1/2 as effective by volume as Halon. 9 times out of 10 when we ask someone who told us they have 'halon' we discover it is actually halotron. Again a brilliant marketing name that fools many. From a cost perspective Element is about 1/2 of a similar halotron on CO2 bottle and 1/3-1/4 of the price of a halon bottle. When you factor in that Element never expires or needs servicing then the value goes up with the passage of time. Again, we hope everyone carries an Element but if not ours please carry something.
I really don't want to get into any arguments about the relative merits of different technologies. I'm not an authority. But as I have said, my understanding is that the "deadly" characterization of Halon does not give a balanced impression of the tradeoffs, which is why I've been inclined to recommend that folks do their own research. I initially dismissed Halon, and ultimately decided that it should not be dismissed...
you may compare what the halon will do and how much poison goes into the air when a car will burn down totally. so what will be more bad?