Is it wise to use a sunscreen during artificial tanning?

No, using a sunscreen will slow down the tanning process, whereas the purpose of using a tanning appliance is to obtain a tan by means of a predetermined tanning course. Sunscreens are used to extend the time during which you can expose yourself to UV radiation. In many countries, manufacturers are required by law to include a warning to this effect in the directions for use of the tanning appliance.