BACKGROUND: Peripheral intravenous catheters (PIVCs) are commonly used devices in emergency departments (EDs), and yet relatively little is known about factors influencing Australian clinicians' adherence to the national PIVC quality and safety Standard. AIMS: To explore attitudes and experiences of ED clinicians around PIVC insertion and care processes. METHODS: This study used an exploratory qualitative approach to analyse written responses to open-ended questions included in an online national (mixed data) survey. Snowballing methods were used to gather responses. Deductive analysis was used to analyse open-ended questions regarding practice and Standard adherence. RESULTS: There were 340 written responses, mainly from nurses in public EDs, who reported suboptimal practices regarding idle catheters, lack of patient participation in care, antecubital fossa insertion, multiple insertion attempts, inadequate site preparation, poor documentation and insufficient review of PIVC. The main factors inhibiting ED clinicians from adhering to the Standard includes inadequate knowledge, perceptions of infeasibility, disbelief in evidence, ambiguous responsibilities, habitual practice, insufficient training, lack of recognition of good practice and inadequate engagement. CONCLUSION: The factors that impact ED clinicians' PIVC Standard adherence are complex and multifactorial. Strategies and interventions are needed to facilitate the implementation of the Standard into daily practice and achieve sustainable behaviour change.