The library is accessible to visitors with day passes during the Institute's regular opening hours (currently Monday through Thursday from 9:00 a.m. to 5:00 p.m. and Friday from 9:00 a.m. to 3:00 p.m.). Visitors who have day passes that are valid for one day only must, however, begin their visits during the library's service hours (currently Monday through Friday from 9:00 to 12:00 a.m., Thursday additionally from 1:00 to 3:30 p.m.). The same applies to the first visit of visitors with day passes that are valid for more than one day (exceptional cases).