How are you?

Do you come here a lot?

Where are you from?

What do you do?

What are your hobbies?

These are all easy and "safe" questions to ask anyone

In the US, breaking the ice is best done by focusing on and being considerate of the other person. 

On a coffee break, you might say to the person sitting next to you.  "What kind of coffee are you drinking?"  Once they reply, you can have follow up questions, or share something about yourself that is relevant to the topic.

**  Note - don't ask yes or no questions, or the conversation can end quickly.

Example:

You:  What kind of coffee are you drinking?

Other Person:  It isn't coffee, it is tea.

Y:  Oh, nice!  I didn't know they sold tea here.

OP:  They don't.  I brought it from home!

Y:  Oh!  That's a good idea.  I might consider doing that.

OP:  It saves a lot of money and I get to drink what I want.

Y:  Exactly.  That's why I bring my lunch sometimes.  It's funny how I never thought of bringing my favorite hot drink with me to work.

This conversation can go on and on...  :)  The next time you see the person, you both feel more comfortable with each other and have now established a small connection over this topic.  :)

Hope this was helpful.  :)