Ok so I'm gaming this new girl at work, I'm getting the following IOIs off her:

Very strong eye contact (Holds eye contact and is always looking at me) when I hold eye contact and smile she smiles back
Plays with her hair when she talks to me
She blushes sometimes when talking to me
She never talks about her boyfriend (she has one)
She adds x's on the end of work emails
She re-initiates conversation when I stop talking
She jumps back to previous threads to initiate conversation again
She qualifies herself

I false disqualified myself in front of her to my work colleagues saying I only date girls 23+ and she's 20.
(The guy was trying to AMOG and DLV me non-stop in front of her but him asking me what my limit on age was actually allowed me to disqualify myself)

Anyway no doubt in my mind that she's attracted.

My question is how do I proceed with this? I've gotta be really careful as I don't want to get in trouble with my boss so I'm a bit careful about kinoing her too.
I really don't want to build too much comfort with her yet in case it lands me in the friends zone.

Cheers!
-AJ.

Should I call her out on it (over chat)?
Basically say I know she fancies me and say I'm cool with it or something?

You sound like you're very much in, HOWEVER -

Be EXTREMELY CAREFUL. This is your job, and there is potentially more than just rejection - termination on grounds of sexual harassment.

_________________
"I want to stand as close to the edge as I can without going over. Out on the edge you see all the kinds of things you can't see from the center."

"I'm going to give you a definite... maybe."

Exactly - any other place and I'd have picked her up already :S
So how would you go about this if you wanted to pick her up in this situation?

Well I called her out on it, I basically said I'm good at reading girl's behaviour and can tell she's attracted to me but I'm totally cool with it and think it's really cute and not to worry as I wouldn't tell anyone at work.

Obviously she was embarressed (as was expected) and she just went really quiet for a few seconds. I gave her plenty of time to disagree but she didn't so I just took that as confirmation that she was attracted. I then just moved the conversation on to a new topic as if it wasn't a big issue to get her comfortable talking again. I give her little kino pings here and there and she doesn't have any negative reaction to them.

I figured using this tactic would reduce any risk of me getting done for sexual harrassment as I haven't directly expressed interest in her yet.
I've helped her put her cards out on the table and perhaps she even feels relieved that she knows I know now?

I was thnking about using this routine nearer valentines day for a Kclose:

A few days before Valentines:

Me: Valentine day's coming up soon, you've gotta get me a card.
Her: (Probably giggle and blush)
Me: No I'm serious - if you get me a card I might even give you something back.

Then on valentines if she gives me a card:

Me: Well I didn't get you a card but I've got something better for you, come here...

Meh I couldn't wait, we're going out on a 'date' next week (don't you just hate that word).

Ok quick question I need help on here - I'm in Comfort with this girl.
When we go out should I start back in attraction or just start from comfort before seduction? Like I said since it's in work I don't kino her much at all...

Dude, quit overthinking this. She likes you, escalate outside the workplace on your date. Sexual Harassment, that's nonsense, just keep it out of the workplace and save it for the date. You'd think nobody was supposed to reproduce anymore, people are so squeamish about it.

One thing to say man

NEVER LOVE THY NEIGHBOR

Last thing you want is scoring a girl and lose your job

Cheers

I NEVER game a coworker, unless is a temporary job and/or in a company so huge that is unlikely I'll meet her often in the future.

Gaming a coworker very often leads to trouble down the road, and I'm not speaking Sexual Harassment, witch is kinda of ridiculous if she's a consenting adult. I'm speaking about a numerous amount of fallout when the "relationship" ends, that can have ripercussions on your job (like uncomfortableness, she start speading voices, she start treating you differently).

There are a lot of chicks out there. Just pick some of the billions ones that are not working with you...