Glass Reactor Over-pressurization Causes Serious Injury to Grad Student Researcher - October 2011

What Happened?
A recent lab accident caused serious injury to a UCB graduate student due to an over pressurization that caused a glass reactor to fail. Glass was sprayed at the researcher who received cuts to his lip, chin, chest, and serious cuts to his hands. 911 was called and the researcher was taken by ambulance to the hospital. The cuts to the hand were serious enough to require stiches and surgery on the palm.

The chemical research involved a toxic/flammable gas that was liquefied and used with a pyrophoric reagent. The reaction was done inside a fume hood, so no one else was affected.

 

Cuts to the hand from glass, required stitches and surgery.

Crushed stirrer and bloodied safety glasses

What was the Cause?
It has not been determined what the exact cause of the accident was. The reactor was flame torched (to ensure dryness), then reactants were introduced and taken to -190°C. It is thought that the thermo cycling of the glass reactor could have weakened the structural integrity and lead to micro fissures of the glass that let in contaminants such as ice water. Another possible cause was that an impurity or contamination was in the closed reactor or on the magnet and may have led to a side reaction which could have caused the rapid exothermic reaction.

What Corrective Action was Taken?
After the accident, the Principal Investigator (PI) immediately closed down the lab for nine days to review their safety procedures. During this time there were various safety investigations and a complete re-training of the research group. The work with toxic/flammable gas did not resume until all safety procedures had been evaluated and implemented.

A Standard Operating Procedure (SOP) had already been prepared for this reaction and it was reviewed to see if it was followed (it was) and how the SOP could be improved.

How can incidents like this be prevented?
It is important to always wear your safety glasses or face shield and other specified PPE. In this case, safety glasses were worn and most likely saved the victim’s eyesight. The lab has a box of safety glasses that must be worn when you enter the lab. The presence of the box of glasses is helpful to remind researchers and visitors that they must wear safety glasses.

Always wear a lab coat when working with hazardous materials. In this case, a lab coat was not being worn and this may have contributed to the cuts to the arms. It was unclear if chemicals were sprayed, but taking off the potentially contaminated lab coat would have minimized chemical contact to the upper torso.

Conduct a careful examination of glassware prior to using it with pressure. Weakening of the lab glassware can happen when it is used, especially at high and low temperatures. In this case, an inspection process and annealing was discussed with experienced glassblowing professional. The lab plans to use a kiln to anneal their glass reactors.

Consider working behind a blast shield or fume hood sash to protect the head and body. The hands might still be exposed, so wearing protective gloves is also necessary. The lab now plans to wear Kevlar/leather gloves and arm sleeves. Researchers can also consider using a tool to be farther from glass reactors.

Consider providing pressure relief. In experiments where pressure may be created, there should be a way to allow accidental pressure to be released so that the reactor does not fail. This is especially important when working with air sensitive chemical compounds.

Work with small quantities of hazardous material. Fortunately, the amount of flammable gas was small (10 mls of liquid) or the injuries might have been more severe.

Resources
To prepare a standard operating procedure (SOP) for hazardous operations see EH&S SOP fact sheet - http://ehs.berkeley.edu/images/ehs/pubs/46labspecificsops.pdf.

For information on safety glasses - http://ehs.berkeley.edu/images/ehs/pubs/25eyeprot.pdf.