You would never use canned air on your camera – why would you use it on your Splicer? The cold rush condenses the moisture in the air and fogs everything. If the internal lens tunnel fogs, only dismantling (or time) will clear it. $$
99% alcohol cleans lenses, v-grooves and mirrors, drug store 70% leaves evaporation streaks as that other 30% (water) is left behind as residue.
Same thing. Need to “dust” debris? Use a bulb, the air is the same moisture level and temperature as that already at the camera lenses. Don’t forget eye protection.