Roommates for Patients receiving chemotherapy

I work on an inpatient oncology unit (now a combined unit for hematology/oncology, gynecology/oncology and benign oncology). Recently, staff questioned the appropriateness of assigning pregnant patients and general OB patients as roommates for patients receiving chemotherapy. The doctors and pharmacists stated they coud not find any concrete evidence to state these patients cannot be roommates and the risk for exposure to chemotherapy is minimal. Has anyone else had this issue or does anyone have advice?

Thanks