Background The effects of open (care provided by general medicine teams with a pulmonary intensivist consultant) vs closed (care provided by a dedicated critical care team) intensive care units on health care workers’ contact with patients and their hand hygiene is uncertain. Objective To determine if closed intensive care units have fewer visits of patients by health care providers and greater hand-washing compliance among providers than do open units. Methods Time-motion analysis was used to observe 2 rooms in a medical intensive care unit at a teaching hospital affiliated with Indiana University School of Medicine, Indianapolis, for 96 hours before and after closure of the unit. The main outcome measures were frequency of health care providers’ visits and their hand-washing hygiene compliance rates. Results Mean number of visits per room per hour by physicians (1.53 in the open unit vs 1.27 in the closed unit; P = .93) and nurses (3.98 in open unit vs 4.14 in closed unit; P = .60) did not differ. No differences were observed in gold-standard hand washing among physicians (0.00% in open unit vs 2.63% in closed unit; P = .11) or nurses (2.50% in open unit vs 3.49% in closed unit; P = .51). However, hand washing decreased significantly in nurses in the closed unit (40.94% in open unit vs 29.84% in closed unit; P = .002). Conclusion Closing the intensive care unit did not decrease the number of contacts between health care providers and patients nor did it increase the providers’ compliance with hand hygiene.