I sincerely enjoy fall. When the summer haze lifts and the sunlight comes in low, the world looks clean, sharp, and new to me. When the daytime temp drops below my sweat threshold, I'll get outside more, and enjoy my little piece of the world. And one evening real soon, I'll be treated to one of my simple fall pleasures, which is smelling a little oak smoke drifting out of a neighbor's fireplace.

Now, some of you might be wondering, "Why doesn't Jowers build his own oak fire, instead of going around sniffing other peoples' fires?" Well, I'll tell you: I live in an 88-year-old house, which has an unlined brick chimney. I'm afraid to burn wood in it, and I don't want to pay somebody a couple thousand dollars to line the chimney with stainless steel, or some high-tech chimney mud. So, don't you know, we Jowerses have gas logs.

Now, some of you chimney sweeps are thinking, "You still need to have your chimney lined! A chimney for gas logs ought to be as good as a chimney for real wood logs!" I know that. But since my gas logs don't make embers that could set my house on fire, and since they don't make flammable creosote, I' m willing to take my chances without the liner. So far, the Jowers gas logs have performed admirably, and they haven't harmed any Jowers human or pet.

I'm not afraid of my own gas logs, but I am afraid of some of the gas log installations I've seen. First on my list: The dreaded vent-free gas logs. Vendors use the term, "vent-free" like it's a good thing to have a fire in your house, and have no vent for it. No, bubba, no. Ventlessness is not a feature. It's a downgrade, and a clear and present danger besides. Fires make carbon monoxide. Carbon monoxide can kill people. That means fires need vents, even cute little gas-log fires.

Even so, if you go to a fireplace shop looking for gas logs, chances are somebody will try to sell you some vent-free gas logs. They'll tell you that the vent-free units are affordable, and people love 'em. They'll tell you that they're safe, and they'll say it's because they have oxygen depletion sensors. I've read the promotional literature for vent-free gas logs, and I know the sensor is supposed to shut off the flame if oxygen in the room gets too low. Problem is, I don't trust oxygen depletion sensors. First of all, I wouldn't bet my life that a cheap add-on gizmo on a set of gas logs will work. Second, people can die from carbon monoxide poisoning in a room that has lots of oxygen in it, as long as there's plenty of carbon monoxide.

Then there's this: Gas fires don't just make carbon monoxide, they make water vapor. Running a vent-free gas log set is a great way to load up your house with excess moisture, and grow a nice crop of mold, mildew, and fungus. Some of those exotic molds can make a person sick.

Another worrisome thing about vent-free gas logs: Hardly a week goes by that I don't see a whopping big set of those logs stuffed into a tiny 80-year-old fireplace. The gas logs hang way out onto the hearth. You people with oversized gas logs, listen to me: It is not OK to have a gas flame burning out on your hearth. Sooner or later, a child, or a pet, or somebody in a bathrobe will walk too close to the fireplace, and end up on fire. If you've got a tiny little fireplace, get some tiny little gas logs. If you shop around, you can find some that will fit into a fireplace that's only nine inches deep.

Better yet, stay away from vent-free gas logs altogether. If you're going to have gas logs, you need a real enough chimney, one that will let the carbon monoxide and the water vapor out. You'll need one other thing: A little clamp on the fireplace damper, to hold the damper open ever so slightly. That way, if you forget to open your damper (as people often do), the flue will still be open. You can buy the little clamps at any fireplace shop.

If you don't have a chimney, but you've just got to have something that looks like a fire, get an electric log set. No gas, no emissions, nothing but honest-to-goodness fake fire. If you want to see a video clip of electric logs (and I know you do), go here: http://www.innohearth.com/elg.html.

If you've got a chimney, and you want gas logs, get the rip-roaring, yellow-flaming, gas-guzzling full-size ones like I've got. Open the chimney damper wide, and max out the gas flame. All that hot air going up the chimney will set up a stack effect, and create one heck of a draft. When you feel the cold air coming in around the windows and doors, do what I do: Crack a window, and you just might catch a whiff of a neighbor's real oak fire.