Lesson Learned - Improper Labeling Causes Injury from Acid Spray

Be extra careful with nitric acid waste!

What happened?
A UC Berkeley researcher was preparing a sample for microscopy. After he had cleaned the sample with isopropanol, he poured the extra isopropanol into a container for unwanted chemicals labeled “isopropanol.” There was an immediate chemical reaction that caused the plastic container to rupture and spray the mixture around the area. He was later surprised to learn that the container actually held concentrated nitric acid in the form of spent copper etchant.

The researcher was startled and called for help. Other researchers promptly came to his assistance and called 911. When he felt a burning sensation on his skin, he washed his body and face in the nearby emergency eyewash and safety shower for approximately five minutes. The UC Police Department (UCPD), the Berkeley Fire Department (BFD), and the Office of Environment, Health & Safety (EH&S) responded. However, the researcher did not wait for these emergency personnel and was escorted by a colleague on foot across campus to the University Health Service (UHS) Tang Center to be medically evaluated. The researcher was later released after being treated for acid burns.acid lesson. jpg

 

Unwanted chemical bottle that blew its top spraying nitric acid on researcher.

Notice that the plastic waste container is tinged blue and labeled 2-propanol. The blue tinge is from "copper etchant." Nitric acid was in the unwanted chemical container, not 2-propanol.

 What was the cause?

This accident happened because the container with unwanted chemicals was improperly labeled with the wrong chemical name. The researcher was not aware that the container labeled 2-propanol actually contained concentrated nitric acid. Nitric acid is a powerful oxidizing acid; explosions can occur when organic chemicals (such as isopropanol) are added to strong oxidizing acids.

What corrective action was taken?
After the accident, the principal investigator (PI) for the laboratory halted research and organized a general cleanup of the laboratory. The storage area for unwanted chemicals was improved immediately by clearly labeling all chemical containers and research samples. Following the investigation and debriefing with the PI, there was a laboratory meeting to discuss improved laboratory safety procedures that included reviewing the chemical hygiene plan.

Lessons Learned


How can incidents like this be prevented?
  • Clearly label unwanted chemical containers. In this case the original 2-propanol label should have been removed or defaced. The container then should have been labeled "unwanted nitric acid."
  • Be especially careful with strong oxidizers (e.g., nitric, sulfuric, perchloric acid, and concentrated hydrogen peroxide). When incompatible chemicals are left in sealed containers, evolving gases can build up sufficient pressure to cause the glass bottles to explode spraying the room with glass shrapnel and liquid acid. In some cases it is useful to use vented caps, or at a minimum leave bottle caps loose until all reactions are completed.
  • Wear personal protective equipment in the laboratory. The laboratory Chemical Hygiene Plan (CHP) contains a personal protective equipment section for researchers to evaluate operations and specify the appropriate protective clothing needed in their laboratories. In this case, this section had not been completed. The researcher should have been wearing goggles and a lab coat. Safety glasses would also help but goggles are preferred. His sight could have been damaged if nitric acid had sprayed into his eyes. It is important to remember to remove your contaminated clothing when using an emergency shower, and to shower for at least fifteen minutes. Stay in the area and continue showering until emergency responders arrive – they will provide blankets for warmth and will transport victims.
  • Wait for responders. The researcher should have waited for emergency responders. Walking to the Tang Center could have exacerbated the injury.
  • Follow-up on concerns identified in the safety inspections. A recent laboratory inspection by EH&S had identified chemical waste labeling as a concern, but the concern had not yet been addressed. Fortunately, the emergency eyewash, also identified as a concern in the self-inspection, was getting flushed regularly and was working properly.

Resources

Specific information on getting rid of chemical waste: Hazardous Waste Program (HWP)

If you have chemical waste concerns or general laboratory safety concerns call EH&S at 642-3073 and your question will be directed to the appropriate specialist.