RO-ILS is designed to improve quality and patient safety in radiation oncology by facilitating shared learning in a non-punitive environment. Higher rates of incident submissions indicate a strong safety culture and support by physicians, who can role model proactive safety culture for team members and trainees. Yet engagement of physicians stands to be improved. We hypothesize that resident versus attending status and select surveyed attitudes predicts RO-ILS utilization. Institutional submissions in RO-ILS between July 1, 2017 and July 1, 2018 were reviewed. In addition, a survey assessing RO-ILS usage, incident reporting to other team members, and attitudes towards submission, was sent to attending and resident physicians in the department. Univariate logistic regression was used to identify if any surveyed attitude’s continuous Likert score predicted direct submission, and if resident versus attending status predicted 1) direct submission, 2) asking another team member to submit incidents (referred submission), or 3) general submission (direct or referred). The multiple testing for attitudes was corrected by Bonferroni method. The association between attitude as a binary categorical variable and direct/general submission was also assessed by chi-squared test. Physicians who self-identified only accounted for 10.7% of all RO-ILS submissions (18/168 total submissions; 5 from residents, 13 from attendings), and these submissions originated from 6 unique physicians (4 attendings, 2 residents) in a department with 13 attendings and 11 residents. The survey was sent to current 12 attendings and 12 residents with a response rate of 83.3% (20/24 physicians); 45% (9/20 respondents) were attendings, 45% (9/20 respondents) reported having ever directly submitted an incident, and 45% (9/20 respondents) reported having ever asked another team member to submit an incident. Of those who referred submissions, 66.7% (6/9 respondents) referred to a therapist or nurse. Avoiding punitive action (OR 0.42, 95% CI 0.14-0.88, p=0.05) and reluctance to submit an incident related to another member of the team (OR 0.51, 95% CI 0.23-0.95, p=0.05) exhibited tendencies for association with submission (Bonferroni threshold p=0.01). Resident status was a borderline significant predictor of less likely to refer submission (OR 0.11, 95% CI 0.01-0.77, p=0.04), and less likely general submission (OR 0.11, 95% CI 0.01-0.73, p=0.03). Attendings are more likely than residents to utilize RO-ILS and ask another team member to submit incidents. The association of RO-ILS use with attitudes of avoiding punitive action and of reluctance to submit incidents related to another team member requires a greater sample size for confirmation.