Hazard Assessments

Hazard Assessments

Chandler Fire Dept

14 years ago, an individual in an organic chemistry lab, placed a half full container of ethyl ether into a refrigerator that was okay to store chemicals, but not rated for flammables. Also stored in this refrigerator was an oxidant. The container sat in the refrigerator, slowly giving off fumes, over the weekend and into Thanksgiving break. Early in the morning, a perfect storm of ingredients mixed together in the refrigerator. Ether fumes, the oxidant and finally a spark from the refrigerator. The result? An explosion that could be heard from a mile away, and a fire that burnt so hot it melted through metal pipes in the ceiling. The laboratory was a total loss. Fortunately the explosion happened when no individuals were present in the building.

Several years ago, in another laboratory, a large glass media bottle was sitting on a hot/stir plate, with N2 being pumped into the bottle under low pressure. Media from this bottle was then being pumped into a bio-reactor. The out-going lines began to clog, so the researchers gently increased the N2 pressure in an attempt to clear the lines. This method had worked in the past. The researcher soon realized this was not going to work, and decided it would be best to take apart the set up and clean the lines by hand. They went to their regulator to turn off the gas, but accidentally turned the regulator pressure valve the wrong way, dramatically increasing pressure to the large glass media bottle. The bottle exploded sending large glass shards into the wall and into the two researchers present. Two individuals went to the hospital with injuries.

I believe there is much to be learned from these two accidents. Both of these accidents could have been prevented. The first accident could have been prevented by having a more suitable storage plan for the flammable liquid or perhaps proper flammables rated cold storage was available but appropriate training on where to store said chemical was not appropriate or followed. For the second accident, lack of training on pressurized systems and not having an engineered fail safe both led to the tragic outcome.

Mind you, the lessons learned stated here are dramatic simplifications, but the point is the same. For those involved in these accidents, they honestly believed they were being safe and following protocol. It is very likely the individual storing the ether in the wrong refrigerator, thought that no harm could possibly come from it. For the second accident, sparging media with an inert gas under low pressure is extremely common place across labs who work with anaerobic media. An accident had never happened before using this method.

So How Do We Avoid Accidents?

Before you start any new experiments you must do a risk assessment. This should be written out in your lab notebook before EVERY experiment and should be approved by your mentor. It does not have to be long or complicated, just a few words about what you are doing to make sure your experiment is safe.

Some things to consider:

  • Does my experiment involve compressed gas?
  • Will my system be pressurized? What can I do to keep my system from being over pressurized?
  • Will I be using toxic chemicals? Do I need a face mask? Respirator?
  • Does my instrument require use of solvents?
  • Will there be a chemical fume hood available?
  • Are there appropriate safety glasses and gloves available?
  • Could I accidently be culturing microorganisms that could hurt me or others in the lab?

Every time you begin a new research procedure, perform the following risk assessment steps and review them with your mentor or lab manager:

  1. You may use this Job Hazard Analysis template  provided by the American Chemical Society.
  2. Use the following documents to help you identify hazards and solutions that you will incorporate into your Job Hazard Analysis.
    1. Common Hazards
    2. Laboratory process risk assessment for a process using a chemical  
    3. Job Hazard Analysis template  
    4. Hazard assessment for a chemicals 
  3. Here is our Center Standard Operating Procedure Template as well: SOP Template.

Remember, just like the example in the video, just because someone else crossed the road, doesn’t mean you shouldn’t also look both ways. You are the first line of defense for your own safety.

Sarah Arrowsmith
Research Laboratory Coordinator