After considering different options of types of heaters for the garage I decided on a diesel heater. I've tried various heaters in past, such as space heaters (too damn noisy) and fan heaters (too damn expensive) so this time I thought I'd try something else.
A guy at work has been using a diesel heater in his garage for years and highly recommended one. So after looking at different models I put in an order for one and to my surprise it was delivered the next day. I set it up on the work bench first just to perform a test run and then figured out where in the garage would be the best place for it. Eventually I decided it was going to sit on the floor next to workbench, although this meant extending the exhaust to the other side of the garage and exiting it through the outside wall.
Now, due to the fact that this heater obviously runs on diesel and has an exhaust I am well aware of the potential problems should anything go wrong that might lead to fumes building up in the garage while I'm in there. So, I took the precaution of buying a carbon monoxide detector and alarm and have mounted it on a shelf in close proximity of the heater so that should any leaks occur, I'll quickly know about it.
At present, the weather has been fairly mild, so I've not really used it yet, but I'm sure that will change in January!