To determine if electronic medical record (EMR) changes and implementation of a study on firearm storage practices changed identification of firearm exposure in children presenting to a pediatric emergency department (PED) with mental health complaints. We also sought to determine the accuracy of information collected on firearm storage practices. Retrospective study of EMR documentation of firearm exposure in PED patients with mental health complaints from January 20, 2015 until November 20, 2017. EMR changes occurred on January 20, 2016 and the firearms study began on February 13, 2016. The primary outcome was documentation of firearm exposure. Secondary outcomes were documentation of unsafe firearm storage practices. We also examined differences between clinical and research documentation of unsafe firearm storage practices post-intervention. We compared groups using descriptive statistics and chi-squared tests. We used statistical process control to examine the relationship between interventions and changes in outcomes. 5582 encounters were examined. Identification of firearm exposure increased from 11 to 17% postintervention. Identification of unsafe storage practices increased from 1.9% to 4.4% across all encounters. Special cause variation in both metrics occurred concurrently with the interventions. Postintervention, unsafe firearms storage practices in firearm owning families were under-identified (39% identified as not triple-safe in clinical data vs 75% in research data). EMR changes and implementation of a firearms study improved identification of firearm exposure and unsafe storage practices in families of PED patients being evaluated for mental health complaints. However, unsafe storage practices continued to be under-identified in firearm-owning families.