A violent reaction occurred while hydrolyzing metal in water. The reactive metal treatment began with a review of the chemical inventory and setup of reaction vessels. The sodium metal was cut in shavings and added one at a time to the reaction vessel. After the second addition, an argon purge was added to disperse hydrogen gas faster. After approximately 10 pieces had been treated, the glass beaker shattered, releasing the contents of the reaction vessel (1 liter) inside the hood and causing the chemist's hand to receive superficial cuts. The process was being performed under a hood with all safety equipment in place. The employee was in personal protective equipment (PPE), but did receive two cuts on his hand through the glove. The treatment of reactive metals was being performed under an emergency treatment permit.
The direct/root cause of this occurrence has been determined to be human error in using a glass beaker to perform the treatment. The decision was made to use a glass beaker in order to viably watch the reactive material being treated. No one had any knowledge that the configuration of using stirrers and the use of a large glass beaker would restrict the release of hydrogen gas as quickly as possible.
On-site personnel performing treatment of reactive metals/chemicals must continue to exercise caution. Although there is an inherent risk in treating reactive metals/chemicals, personnel must adhere to conduct of operations principles to include conducting a formal pre-evolutionary briefing. During the briefing, a review of the job safety analysis and/or other applicable policies/procedures should be discussed to ensure strict compliance with all safety precautions associated with personnel protection. Prior to commencement of treatment processes, laboratory hoods must be designed with appropriate blast shielding or other pre-determined engineering safety features.