Safety First

I recently stumbled across a Google+ feed from a law firm handling a lawsuit for a young man injured in an accident in a New York classroom. A teacher was demonstrating the visible colors produced when various metal cations are excited by heating. In the case cited, the teacher was using methanol ignited in Petri dishes. When the teacher attempted to repeat the demonstration, the methanol in the stock container from which she was pouring ignited, shooting flames across the room, and burning two students.

The most tragic part of the case is that this particular demonstration has resulted in serious burn injuries in numerous classrooms in recent years, and there have been constant warnings against doing “The Rainbow Demonstration”.

The teacher in the classroom had a Master’s degree in chemistry, but there is a tremendous difference between the knowledge required to obtain such a degree, and the knowledge required to safely lead demonstrations and lab activities for students. So, what went wrong?

  1. The teacher used methanol instead of ethanol. Methanol is more volatile, has a lower flash point, and should not be ignited in any classroom demonstration. The use of methanol in the “Rainbow” experiment and the “Woosh bottle” demonstration has repeatedly resulted in catastrophic injury.
  2. The teacher filled the Petri dishes from a large stock bottle of methanol. Stock bottles belong in dedicated flammables storage. Only the exact quantity needed should be brought into the classroom.
  3. The teacher, probably in response to the student request to “do it again!” poured the methanol from the stock bottle into Petri dishes that were almost certainly very hot from the previous combustion.
  4. There was no fire blanket in the room.

You can read the actual results of the investigation into the accident HERE.

Please take the time to view this YouTube video featuring a young woman whose life was forever changed when she was injured in a very similar accident. And PLEASE commit to never igniting methanol in a classroom environment.

 

Published by

Andy Allan

I am the owner-developer of Sciencegeek.net and a science teacher at El Diamante High School in Visalia, CA.