Restrict Descriptive Flexfield Segment to Operating Unit

Hello

Is it possible to restrict a particular Descriptive Flexfield Segment to Operating Unit ?

For Example:

ForExpense Report Lines, I'm creating code Airfare. Under Airfare, we have additional fields such as Location From, To and Travel Provider used.

I want to restrict one of the values to be displayed only under one Operating Unit.

Is that possible ?

I tried going into personalizations, but the additional information does not show up under personalization.

Any help would be appreicated !

Thanks

Len