Oversight In Transcription Of Written Procedures Causes Explosion – March 2016

What happened?

On March 10, 2016 in a chemistry research lab an undergraduate research student was injured and required medical attention when a glass scintillation vial exploded. The vial exploded while the student was collecting a dry precipitate powder with a metal spatula. The lab was evacuated and the Texas Tech Police Department and the Lubbock Fire Department responded to secure the lab and transport the student to the hospital. Injuries were superficial and the student was back in class the next day.

The student was, appropriately, not working alone and all personnel in the laboratory were wearing appropriate personal protective equipment including lab coats, safety goggles and gloves.

What was the cause?

The cause of the accident is believed to be an omission of a hydrochloric acid precipitation step during the recreation of a synthesis reaction taken from literature. This allowed the unintentional formation of a diazonium salt that exploded during collection for further analysis.

What caused the incident?

• Unanticipated formation of an explosive salt compound as a result of a transcription error from a previously published procedure.
• Salt was collected with a metal spatula initiating explosion.

What corrective actions were taken?

When fire and police personnel released the lab, Environmental Health and Safety (EH&S) staff conducted a cleanup and investigation and released the lab fourteen days later. The investigation included two recommendations which are provided below:

1. Researchers working on synthesis reactions with anticipated energetic products or intermediates need to be cautious of products created during the reaction series. As part of a regular hazard analysis conducted at the outset of experimental work, researchers should review and update their Standard Operating Procedures (SOPs) to incorporate the possible hazard(s) of intermediate products. In this case, the intermediate product should have been identified as energetic on the basis of the reaction series being run.
2. All work with potentially energetic materials should be performed with anti-static plastic tools to reduce the possibility of friction and static discharge creating an initiating spark.

EH&S staff met with the Institutional Laboratory Safety Committee and the Principal Investigator involved to convey these recommendations and review updated procedures.

How can we prevent incidents like this?

• As part of regular hazard analyses conducted at the outset of experimental work, examine all chemical synthesis reactions as to the possibility of energetic byproducts and intermediates. If byproducts or intermediates are a possibility, update all relevant SOPs so unintentional products will be handled with universal precautions (i.e., assumed as energetic until proven otherwise).

Resources

1. Section 11 of the TTU Chemical Hygiene Plan