This research examines whether using a reference tool alters the monitoring of the mechanical index (MI) and thermal index (TI) during obstetric (OB) sonograms. A presurvey regarding users’ behavior patterns of monitoring MI/TI indices was emailed to sonographers who were registered in a clinical database affiliated with an accredited sonography program. The presurvey included a reference tool which respondents were asked to print and use when performing OB sonograms. A postsurvey was sent to the same respondents to determine if behavior patterns regarding MI/TI monitoring improved after using the reference tool. There were no significant changes in how often sonographers monitored MI/TI from the pre- to the postsurvey.