Lessons Learned

Reports on incidents that involve injury, exposure (real or potential), or significant damage property. Lessons Learned detail what happened and how similar incidents can be avoided in the future.

Vacuum Chamber Over-pressurization

Lessons Learned

Pressurized systems hold a great deal of energy. Over-pressurizing a chamber can cause adverse effects such as the view window rupturing. Care should be taken when returning these to atmosphere.

To prevent similar incidents, follow the recommended guidelines below:

Pressure relief valves and additional personal protective equipment (PPE) can be important safety measures in the event of a system failure. A SOP should be written for hazardous processes based on a hazard analysis.

For additional assistance, contact EH&S at...

Laser Eye Exposure from a 1 Watt Class 4 Laser Beam

January 5, 2022
Office of Environment, Health, and Safety
What happened?

A researcher was exposed to a 1 watt continuous wave beam from a Ti-Sapphire (852 nm) laser while visually inspecting a non-linear crystal on the optical table with a dielectric mirror. The researcher was unaware that the beam was present and it was directed into their right eye. The researcher was not wearing laser eye protection because they thought the laser was off.

Shortly after finishing the visual inspection, the researcher noticed a spot in their field of vision and realized that they had been exposed to the 852 nm laser beam. The researcher was seen at the...

Electrical Fire Caused by Heat Gun Connected to Power Strip

March 6, 2025
Office of Environment, Health, and Safety
What happened?

A small fire broke out in a laboratory in the Department of Physics when a service technician plugged a heat gun into a power strip that was plugged into an isolation transformer. When a transformer is overloaded, the transformer can experience high operating temperatures, causing it to overheat. In this case, the overheated transformer caused a small fire to break out.

Fortunately, there were no injuries and damage was very minimal. The service technician notified the lab manager as soon as they noticed smoke. The Lab Manager...

Resources and Guides

Job Safety Analysis (JSA)

A JSA describes job tasks in step-by-step fashion, identifies associated hazards at each step, and outlines proper hazard controls that minimize the risk of injury or illness to the individual(s) performing that task.

JSAs Listed by Topic: Body Mechanics ...

Lessons Learned: Fume Hood Vessel Overpressurization and Skin Burns from Heating Glass

October 2, 2023
Office of Environment, Health, and Safety

The following lessons learned reports detail what went wrong and what corrective actions have been taken or will take place to address the incidents.

Improper Labeling Causes Injury from Acid Spray

September 30, 2004
Office of Environment, Health, and Safety
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...

Employee's Toes Crushed by Falling Compressed Gas Cylinder

March 31, 2007
Office of Environment, Health, and Safety
What Happened?

In February 2007, a University of California, Berkeley (UC Berkeley) researcher was loading a gas cylinder on a two-cylinder cart when the previously loaded cylinder fell and crushed his toes.

What was the cause of the accident? What were the contributing factors?

The most likely cause of this accident is the fact that this two-cylinder cart had no means to secure both cylinders independently. Therefore, when positioning the second cylinder on the cart, there was no way to secure the first cylinder. Loading the second cylinder puts the...

Job Safety Analysis (JSA) Library

Job Safety Analysis (JSA)

A JSA describes job tasks in step-by-step fashion, identifies associated hazards at each step, and outlines proper hazard controls that minimize the risk of injury or illness to the individual(s) performing that task.

Fact Sheets

Fact Sheets

EH&S Fact Sheets serve as campus-wide Standard Operating Procedures (SOP).

Lessons Learned at UC Berkeley