A methodological study was conducted to test the validity and reliability of the patient safety (PS) scale developed by Rashid (2007) for evaluating nurses' perception of adult intensive care unit (ICU) design features related to patient safety. Data for the study were collected using a Web-based survey instrument. A link to the survey instrument was posted on the Web site of American Association of Critical-Care Nurses (AACN) for ICU nurses in different US states to participate. A sample of 587 valid responses was divided into 2 halves for cross-validation. The first half of the sample was used for exploratory factor analysis and the second half for confirmatory factor analysis. This method was applied to identify any latent factor structure in the PS scale. Based on the factor analyses, 4 relevant PS subscales—Efficient Work Process, Patient Room, Accessibility and Visibility, and Maintain Sterility—were identified. These PS subscales were used to investigate whether ICU unit characteristics, nurse characteristics, and hospital type affected nurses' perception of ICU design features in relation to patient safety. The study shows that nurses' perception of ICU design features related to patient safety can be influenced by such factors as nurse characteristics and unit characteristics. When using the scales, therefore, the designers can be aware of the influence of these external factors on nurses' perception. It is hoped that the PS subscales evaluating nurses' perception of ICU physical environmental features related to patient safety would help designers and health care personnel make better ICU design choices.