I've always used canned air and never had a problem with any reader. Of course don't keep blowing the air under the bezel after it starts to feel very cold from propellant, usually holding it perfectly upright gives you the longest time the air will remain warm, don't tip the can at all or hold it sideways. DSLR blowers often have a soft brush attached, so that will be safe to use as well.
I always use a cover with my readers, it's so much easier to just flip the cover closed and not have to bother turning off any switch, then just open again to read. Doing that also means far less wear and tear on the switch. The cover should always put the reader into sleep mode when you close it. You can still peek under it to double check that the light has gone off if you still want to
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