It happened again:
A reminder that the American Chemical Society's Committee on Chemical Safety "recommends that the “Rainbow” demonstration on open benches involving the use of flammable solvents such as methanol be discontinued immediately due to extreme risk of flash fires and flame jetting."
GREENSBORO, N.C. — A Western Guilford High School student is in the hospital after an explosion in her chemistry class Wednesday. Aimee Green, 16, is a junior at the high school. She is listed in good condition at Wake Forest Baptist Medical Center, according to a spokesperson.
“Please pray for our beautiful daughter Aimee Green. She was in chemistry today, and the teacher was doing an experiment. It went badly and exploded. The explosion went right onto Aimee, and caught her hair, face, chest and arm on fire,” Aimee’s mom, Alicia Coverston Green, wrote on Facebook.
The experiment involved ethanol, alcohol and salt, Green said.
Green said her daughter was admitted to the burn ICU on Friday for fluid resuscitation, pain control and wound care.
Another student was injured but not as badly, officials with the school district said.Other reports indicate that it could not be confirmed that the student was wearing PPE.
A reminder that the American Chemical Society's Committee on Chemical Safety "recommends that the “Rainbow” demonstration on open benches involving the use of flammable solvents such as methanol be discontinued immediately due to extreme risk of flash fires and flame jetting."
I suspect that not many chemistry teachers are members of the American Chemical Society and thus would be unlikely to see information about the Rainbow demo.
ReplyDeletePerhaps ACS could email a link to that flame test page to every middle school and high school in the country, requesting that the email be forwarded to all chemistry teachers.
That likely won't work either. My institution's student club groups keep doing the Rainbow demo and when advised they shouldn't and shown the ACS/CSB info regarding the demo, they dismiss it because "It won't happen to us/Nothing bad has happened before/You're not our advisor/You aren't a PhD/etc"
DeleteUgh, when will teachers stop being stupid?
ReplyDeleteWhen will EMPLOYERS start requiring proper safe practices and provide safety education?
DeleteI'm surprised that high school chemistry labs still exist in 2019. Pretty much every other remotely dangerous activity I did in school has been eliminated (including slightly dangerous activities where the risk/reward balance makes sense). I'm concerned that schools are going to respond to this in the most CYA manner possible - by eliminating the lab component of chemistry classes rather than paying more attention to teacher training and lab safety.
ReplyDeleteThere is a very specific cause of these accidents - pouring alcohol from a bottle into an already lit flame. Why not spread the word about how to do these demonstrations safely instead of having the knee-jerk reaction to stop it entirely?
ReplyDeleteI dunno, I can't figure it out: https://www.cbs46.com/news/investigators-chemistry-teacher-froze-in-pure-shock-when-student-caught/article_9cbd8020-00e1-11ea-aad8-bb2f266ecfca.html
DeleteFlippant responses aside, I think we have sufficient evidence to indicate that the average teacher with average levels of training cannot handle these experiments without injuring (SWAG here) 1-5 students a year. https://docs.google.com/spreadsheets/d/1my-HReA3m117ux4GKwlP0jMGbDmmyGG1X-H818RIRzE/edit?usp=sharing
DeleteThis is WITH a $60 million settlement coming out of NYC, one of the most prominent school districts in the country with in the biggest media market in the country.
If you mean rainbow demos in general, there are other ways to do them without pouring flammable liquids around a flame (soak sticks in salt solutions and light the sticks on fire), so it doesn't require people to stop doing this type of experiment. The classical rainbow experiment, though, has had more than enough serious burns involved with it to consider it anathema (you'd figure serious and disfiguring burns, let alone multimillion dollar damage awards, might give someone pause).
DeleteBasically, the risk for this experiment as performed is relatively high while the reward is nil (because you can achieve the same ends with far lower risks). Why do it? Mostly, the people doing it either aren't thinking about it very much ahead or have done it forever and haven't thought about its risks and rewards. Neither of those is an indicator that the people doing this version of the rainbow demo have thought about how to deal with the safety issues or how they can best convey the information and emotions involved with the experiment, and that fits with the general theme that this implementation is a really bad way to do this demo.
It seems that if we can spread the word about not doing this demo, we can just as easily get the message out there that there are specific risks that need to be avoided. It's a bit absurd to suggest that people teaching chemistry at any level should be incapable of safely burning a small amount of alcohol in a metal dish (literally something that I figured out how to do as a teenager with things from the local hardware store). And there is value to it. The effect produced is noticeably more visually enticing and stimulating than briefly placing a salt-covered stick in a flame. So let's spread the message that it's critical to not pour flammable liquid onto an already lit fire. We should be educating people about how to do things right, not cowering at any possibility of danger. It might seem like it does not matter that much, and that's kind of true for a single chemistry demo, but the attitude of moving to ban or otherwise end anything remotely hazardous ultimately does a disservice to students. If we teach them to be this fearful about something like this, is it any wonder that we have students who make it to college (or beyond) without knowing how to do lab work safely? or beyond just students going into chemistry, is it a wonder that our societies are filled with people who fear things like nuclear power and GMO's?
DeleteI don't think we're going to convince each other here, but I want to make one technical point, A7:21, assuming that you're also A12:39PM. You say the specific risk is "pouring alcohol from a bottle into an already lit flame".
DeleteThis is not quite correct - I would refine it to "pour bulk alcohol (any amount larger than, say, 1 mL) into the dish." Often, the flames of the rainbow demonstration are invisible because of the use of methanol.
In fact, I would further refine it to say that "there shall be no bulk methanol in the room during the performance of the demonstration."
Finally, these are the thoughts of a random chemist on the internet who has followed this issue for far too long (since 2014, IIRC). For future people who come across this discussion, the best practices for this demonstration are summarized in this article: https://cen.acs.org/articles/93/i46/Make-Chemistry-Classroom-Demonstrations-Experiments.html
I know this can vary between colleges and states, but at my undergrad, the upper-level chemistry courses were removed from the high-school teaching chemistry major track to make room for all the education courses. I suspect this is the root cause of the problem.
DeleteSad times we live in when there's a call to "spread the message that it's critical to not pour flammable liquid onto an already lit fire."
DeleteIt doesn't take a whole lot of chemistry education to 1) not set flammable liquids on fire and 2) to think about what you're doing, what its hazards are, and how to mitigate them (the hazards aren't chemistry-specific). If you don't think about what you're doing, you can find lots of ways to cause chaos and hurt people. While the open liquid rainbow demo seems to not be impressive enough for the hazards it creates, the hazards could be managed without a whole lot of chemistry knowledge. You do have to think and prepare for what you do, though, and more chemistry education won't make you do that.
ReplyDelete