QtM, I totally forgot that you worked in a prison, as a doctor no less! I could have just asked you I guess. Duh. Anyway the general impression I’m getting here is that the reason smoking is allowed is some prisons still, is that either the employees are bitching about a ban, or the entity that runs the prison just hasn’t gotten around to banning smoking yet. Unless there’s anything wrong with that, I guess my curiosity is sated.
But then we wouldn’t have had this interesting and entertaining thread! And I’m such an attention whore that if my opinions aren’t seen by the teeming millions, then what’s the point of me offering them? 
Aside from the whole health issue and the just plain nastiness of tobacco, I’ve always wondered about a more important issue. Why are prisoners allowed to have fire? Isn’t that like allowing them to have knives? And as for knives, is the lunch room limited to plasticware?
I suppose that’s a good point… but tobacco is a whole lot more addicting than alcohol… but…
I realize you’re not being serious with this comment, but it brings up another point about why smoking is being banned in some prisons: health care costs. It’s rather expensive to treat an inmate for lung cancer, especially since recent court decisions in some states have decreed that inmates should have top-of-the-line drugs and treatments. (Before, they were treated for their diseases, just not with the best-of-the-best, latest, most expensive options.)
In this day and age, when prisions are closing, staff being laid off, and valuable programs being scrapped because of budget cuts, it makes sense to try to keep medical costs down by keeping the inmates (as well as the staff, who have state-paid medical insurance) as healthy as possible.
You might be surprised what sort of dangerous impliments some inmates have access to. In the prison in which my husband works, the inmates work in various industries, such as upholstering, which require allowing them access to a variety of sharp tools. (They are monitored while using them, and the tools are counted at the end of the shift to ensure that none have “wandered off”.) Inmates also work on the maintenance crew and in the kitchens, allowing them use of shears and butcher knives and whatnot.
Fire isn’t really a big concern. Most prisons are realatively fire retardant. There isn’t any carpet or curtains, and most prisons have fire suppresion equipment. An inmate can set his clothing and bedding on fire, I suppose, but it would be quickly contained. It would take a great deal of concentrated effort to make a really dangerous fire. Add to this that a good deal of long-termers see the dorms as their homes and have little interest in seeing all of their worldly goods burned up, and fire becomes one of your smaller worries.