Good idea. It depends a lot on the culture of the company, and what you’ve said makes me think that the culture of your company is strongly against this. My old boss met his wife at another location of my old company, and they’ve been married for 30 years. She even transfered into our center. But I’ve also worked at places which would frown on it. I would also guess that you were being a bit more obvious than you think you were. 
My company has the policy where you can ask a co-worker out on a date once, any more will be considered harassment.
I assume that means “ask her once, and if she says ‘no’ you can’t keep re-asking”.
It’d be strange if the policy is that you’re allowed just one date with a co-worker in your entire career with the company (which is how I first parsed your post–cut me some slack, the caffeine doesn’t work like it used to. 
).
Cheers,
bcg