Background <p>Healthcare Associated Infections generate a high cost in healthcare systems. The Infection Risk Scan (IRIS) tool may be a suitable tool to assess the quality of infection prevention measures in Intensive Care Units (ICU). The aims are to identify individual risk factors in patients and quantify the degree of non-compliance with measures to prevent healthcare-associated infections using the IRIS method in an ICU.</p> Methods <p>It is an observational and cross-sectional study. The method was piloted in 8 beds and subsequently in 32 beds in a tertiary hospital. Adult patients (&gt; 18 years) admitted to ICU during the study and healthcare staff belonging to the ICU. Risk of infection and adherence to prevention measures were measured. The IRIS consists of two parts called risk profile and improvement chart. In the first, variables related to the patient’s history and susceptibility to acquiring a healthcare-associated infection were studied, and in the second, the adequacy of procedures performed on the patient or their environment, considered important indicators for infection control, were assessed.</p> Results <p>Critically ill patients had a high use of invasive devices such as central venous catheters, urinary catheters and invasive mechanical ventilation. Adherence to healthcare-associated infection prevention measures could be improved due to high non-compliance with hand hygiene (48% non-compliance in the first measurement and 55.6% in the second measurement), non-compliance with hygiene recommendations among healthcare workers (&gt; 4 workers wore at least a wristband and/or wristwatch in the second measurement) and insufficient cleaning and disinfection of surfaces and equipment in both measurements (some surfaces were completely clean).</p> Conclusion <p>The IRIS provides comprehensive information on the quality of infection prevention measures and offers an opportunity for focused improvement in infection control based on the results of the improvement chart.</p>