Abstract: At 10:15 a.m. on September 28, 2012, an employee was working as a plater for Hartwell Corporation, a manufacturer of latching systems for aircraft, in Rancho Cucamonga, CA. The employee had worked for the employer for 5 years. He was preparing a solution to add to alkaline etchant tank Number E-1 in the plating department. The employee had a 5-gallon (19-liter, 4.2-imperial gallon) bucket with Aluminum Etch 108 powder and another 5-gallon (19-liter, 4.2-imperial gallon) bucket with water. The employee poured some Aluminum Etch 108 powder into the water bucket while stirring. A clump of powder fell into the water bucket, and the mixture overflowed from the bucket and splashed onto his legs. The employee ran to the restroom, removed his pants, and wiped down his legs with wet paper towels. The employee rinsed his pants with water and put them back on. The employee left the site to go home to change his clothes. The site's lead person spoke to the employee on the phone and instructed him to call emergency medical services, as the employee was not feeling well. The employee did not call emergency medical services. Instead, a neighbor took him to the Chino Valley Medical Center. The employee was treated and released on the same day, with an instruction to go to the Arrowhead Regional Medical Center for a follow-up. On October 1, 2012, the employee went to the hospital as instructed. He was admitted for hospitalization for 9 days for third-degree chemical burns on both legs. The employee was wearing safety glasses, chemical-resistant gloves, and steel toe boots at the time of incident. He did not wear a chemical-resistant apron, which was provided by the employer. Aluminum Etch 108 is dry solid mixture that contains more than 50 percent sodium hydroxide. The incident was caused by the employee's failure to wear body protection while handling a hazardous substance. The incident was reported to the DOSH West Covina District office by the company's EHS Coordinator at 2:00 p.m. on October 1, 2012.