Is it safe to vacuum my PC with a normal household Vacuum cleaner?

My desktop PC gets very dusty and I'm just wondering whether I can damage my pc when sucking all the dust away?
Update: PS: I'm not talking about sweeping the nozzle right on the components, just sucking up dustballs, so the nozzle won't make contact with the parts. I do this all the time on my own pcs but my friend's pc won't boot, it is just old or did the vacuum damage it?
Update 2: Obviously, the PC is off and I check if anything is loose before I vacuum, I'm just wondering whether air can damage components?
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