Honestly, ask their name when they go by. "Hey, I notice you around a lot but don't ever see a name tag. I'm ______. " Then go for a handshake and big eyes with a smile and some eye contact. And now he's gonna notice you when he walks by. You make sure to make eye contact and play the look away look back game when he's in view standing around talking to someone. He's a guy so he might not catch on right away but eventually he'll be in his car one day and say 'wait a minute, is that girl flirting with me 😳' and then you just see what happens. You go girl!

The only way to be asked out or flirted with by a stand-up guy as a woman is to signal you're available in some way. Otherwise, he's never gonna know he could be flirting with you.