BACKGROUND: Health care-associated infections pose a significant risk for the patients in intensive care due to the use of medical instrumentation required for care. METHODS: We conducted a cross-sectional, nationwide survey on awareness of recommended infection prevention practices involving central venous catheters and invasive ventilators in intensive care units. RESULTS: A total of 810 (50% of those surveyed) nurses and physicians participated in the survey. We found that 8% of the respondents had good knowledge of infection prevention in central venous care, while 24% had good knowledge of ventilator-associated pneumonia prevention practices. DISCUSSION: The overall level of knowledge measured with this nationwide survey was suboptimal. The level varied between units, and depending on individual questions for particular professions. The displayed knowledge may have partially been based on tradition rather than on up-to-date evidence-based guidelines. CONCLUSIONS: Educational training in evidence-based infection prevention is needed for practical implementation to be improved.