My colleague has been diagnosed with active tb. do i and the staff need to get tested?

Yes: Everybody gets tested to track the spread from one "index case" so that the spread is stopped. Testing varies by country because some countries use blood tests, some use skin tests, etc. The public health department should be interviewing and testing all involved persons. The types of person-to-person contact, the duration of contact, plus the age of the persons, all are important.