This is a supplement to our calculator Thermometer Error.
If you want to use a value for the two-point calibration that is not as low as the freezing point of water, in addition to the boiling point of water, and secondly take into account a thermometer placement that may not be ideal, you can use the boiling point of high-abv ethanol. High-abv because then one knows quite precisely the alcohol content in the vapor and the boiling point. Moreover, the alcohol content of the vapor then hardly changes during distillation. So ideally, you should have rectified alcohol with 95 or more %abv. But not alcohol that has been fortified to above azeotrope using special methods. This is because our boiling point data only goes up to the azeotrope.
This thermometer error can be entered into our calculators in the same way as that determined by a water vapor distillation and ice water measurement, and is then taken into account in the calculation. It is more suitable for measurements in the vapor path than the conventional one. However, if you want to use the thermometer to measure the distillate temperature to correct the temperature of the alcohol content, for example, the conventional one is better suited. Or you can do both and use two different thermometer errors depending on the situation.
Since one does not carry out both distillations at the same time, the local air pressure for both distillations must be entered into the computer.

Explosion and fire hazard:
If vapors escape, they are highly explosive. Depending on the concentration, a spark is enough to ignite them. The distillate also ignites immediately on contact with a flame. This flame may then travel up the cooler into the still and ignite the vapor there. Hobby stills are often not perfectly sealed.

1. The still should not be heated by a flame. Of course, no other flames should be in the vicinity.
2. Optimize the sealings of the still.
3. Ventilate the room permanently during distillation.
4. Wear protective clothing. Every part of the body must be covered. Especially the eyes and hands.
5. Have a suitable fire extinguisher ready. Powder, foam and CO₂ extinguishers are suitable. Before buying an extinguisher, be well informed about the advantages and disadvantages of each type.
6. Cool down the distillate well and, if possible, collect it in such a way that little evaporates into the air you breathe. Of course, do not close the distillate outlet when doing this.
7. If there is an odor of alcohol, immediately turn off the heating, let the cooling continue, leave the room and wait for the contents of the still to cool down.
8. Even after a successful distillation, let the still cool down by itself and empty the contents only when it has reached room temperature.