Some cautionary notes as well for the home (any) roaster
1. Put the roaster on an RCD
2. If the roaster is gas, definitely flue it properly and I would even go so far as to suggest you get a carbon monoxide detector (cost around £15) and place it in a suitable location in the room you roasting in
3. Make sure you have a suitable fire extinguisher
4. Have a heatproof pair of gloves to hand (and I mean heat proof!). You might need to handle a very hot object and move it or do something to it in a hurry.
5. If you roast (on any type of roaster) at night or in the dark, it is ABSOLUTELY ESSENTIAL to do it next to a rechargeable light source that will come on automatically should the power fail. This leaves you both hands free to make the roaster safe. Some beans/roasters roasters very near to the end of the roast could catch fire if the power fails, because the airflow stops, but the element is still hot. If I am wrong about this it’s cost you a few pounds, if I am right, it could save your life. Personally I use a rechargeable emergency light (dual 18W fluorescent tubes) wall mounted (it's also removable), right next to the business end of my roaster. If the power fails on this will switch on automatically and give 36W of light for an hour or more. Being fluorescent the light is equivalent to that given by a 100 watt light bulb. Mine was purchased from Halfords for a very reasonable £15
6. Try and ensure someone knows where you are and what you’re doing!