This report presents a detailed investigation of a workplace health and safety (WHS) incident, covering various aspects from procedures and factors to legislation and incident reporting. It begins with an overview of investigation procedures, including the steps involved in health and safety investigations, sections found in a procedure, and factors related to chemical spills. The report then delves into relevant Australian legislation, specifically focusing on Western Australia, and outlines obligations regarding incident notification to government authorities. It further examines actions to ensure workplace integrity, evidence preservation, and the registration of incident information. The report also explains the severity, sensitivity, and technical aspects of workplace incidents, differentiating between small and serious injuries. It provides a list of legal obligations, required resources, and potential barriers to investigation, along with a draft action plan. Furthermore, it explores methods for obtaining information, determining incident causes, and implementing risk control plans. Finally, the report details the design of an incident report and outlines the dissemination of investigation results.