Chemical Forums
Specialty Chemistry Forums => Chemical Education and Careers => Topic started by: jasongnome on September 06, 2017, 04:54:19 AM
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This is a pet hate of mine and I was wondering what others think.
Firstly, some background, I've been a science teacher for nearly 20 years, before that I worked in a hospital microbiology lab so I am very aware of the need for genuine safety in the lab.
I make my students wear safety glasses if they're heating anything in an open beaker or tube, even water, or using any chemicals that are even vaguely hazardous.
However, I'm seeing a HUGE increase in safety instructions on worksheets etc prepared for schools with really SILLY safety warnings. I hate this, I think it's counter-productive. I want my students to know that if I give them a safety instruction it's because it's sensible. Stupid warnings, when they know something is safe is just like the story about the boy that cried wolf.
Here's an example from 2011.
http://sites.jmu.edu/chemdemo/2011/06/14/mm-color-wheel/
In this demo suitable for younger students, all you use are cold water, M&Ms and a plastic petri dish, yet it tells them to wear safety glasses.
Why?
Do they use safety glasses to drink water or eat M&Ms outside the lab? Of course not, so they KNOW this experiment isn't hazardous in any way whatsoever, they know there is nothing to protect their eyes from.
I don't buy the argument that they should be in the habit of ALWAYS wearing them in the lab either, that's a nonsense, they should be taught to properly assess safety. I don't make them wear saftey glasses to write with pens during a theory lesson, why would I make them when they're just dissolving M&Ms in water?
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I agree regarding over the top warnings... Some of the labels we have to put on things now at work are way over the top for the level of hazard.... as you said - it's like crying wolf... when we DO get something that needs a lot of care the hazard warnings are not different from stuff that is pretty safe. It's gone so far as to be actually dangerous as people don't give the warnings as much respect anymore. EVERY safety data sheet for tins of paint has warnings all over it.. most of the time people ignore these... but when they are actually genuine, people ignore them anyway as they assume it is just over kill on the safety notice to cover the manufacturer.
Regarding the water and M&Ms though I would argue that they should wear safety spec for ALL experiments in case of unknowns.... they re in a lab - a place with hazards... what if the water was acid in an unlabelled beaker that someone left out and it reacted with the chocolate and spat up an acidy piece of chocolate into a kids eye. ;-) What if someone else in the lab has a spam whilst carrying acid and threw it across the room without warning. Their experiment might be safe, but is everything else around them in a lab environment? ;D
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Everyone wears safety glasses in a lab at all times.
Its what you do. Its the outfit. It means you came in to do some work, and when you leave, you take them off and you're not ready for work, and no one should bother you in the hallway for "oh, just a quick thing in here." Nope. You took off the safety glasses, its now bathroom or snack time or flirting time or cel phone time or I just gotta fart time. There is no overlap between these situations. So the eye wear is part of the "uniform" for the task.
P has it correct in the second part, you don't know what's happening elsewhere in the lab, or what mistaken labels there are hiding other hazards.
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Don't kids love wearing safety glasses? Isn't it fun to play scientist? Don't you have a bunch of little white lab coats for them to wear? Don't they love it?
Anyone? Anyone? Bueler? Anyone?
When I was in college, I used to bring the deli jackets from my high school job to class lab. I felt so grown up.
OK, jasongnome:, here's a plan. Everyone wears lab safety glasses, no one does without in the lab, and they don't swing them on their fingers, or wear them on the backs of their heads as a joke.
The students who help you setup get to wear a white coat the whole class. (Don't tell the you got it from a delicatessen.) You select them on the basis of their other work. Completed written pre-labs, or their knowledge of the experiment to be done when verbally quizzed. Those kids you want to encourage to advance. As it stands, your original post is just going to give ammunition to the slacker kids who want to fool around even worse than not wearing safety glasses for the M&M experiment.
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In the case of junior scientists - they don't have the experience to do a proper risk assessment. M&Ms and water may not have any known hazards, but other experiments might. At what level of danger is it appropriate to not wear safety goggles or coats? Who makes that determination? It's best to get young scientists in the habit of wearing PPE whenever they are in the lab, regardless of what they think the danger level is.
And, as mentioned elsewhere, in a real laboratory there typically isn't just your own experiment going on. You may not be doing anything hazardous but the person next to you or behind you might be. Shrapnel flies, fumes diffuse, acid sprays, and so on. So again, I think there's a good lesson for students to always wear PPE no matter what they are doing. It will pay back later on when putting on eye wear and lab coat becomes automatic.
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Regarding the water and M&Ms though I would argue that they should wear safety spec for ALL experiments in case of unknowns.... they re in a lab - a place with hazards... what if the water was acid in an unlabelled beaker that someone left out and it reacted with the chocolate and spat up an acidy piece of chocolate into a kids eye. ;-) What if someone else in the lab has a spam whilst carrying acid and threw it across the room without warning. Their experiment might be safe, but is everything else around them in a lab environment? ;D
Firstly, for a simple experiment like this we'd be using water from the tap (fawcet for Americans), secondly, I wouldn't have other students in the room walking around with acid while I had younger students doing this! ;)
If I DID have other experiments going on, then THAT would be the reason for the goggles, which would be made clear.
As for unknowns, I agree on that, my GCSE students (14-16yo) have to be able to identify an unknown salt. I expect their safety precautions to assume it's the most hazardous one out of the options.
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Don't kids love wearing safety glasses? Isn't it fun to play scientist? Don't you have a bunch of little white lab coats for them to wear? Don't they love it?
Anyone? Anyone? Bueler? Anyone?
When I was in college, I used to bring the deli jackets from my high school job to class lab. I felt so grown up.
OK, jasongnome:, here's a plan. Everyone wears lab safety glasses, no one does without in the lab, and they don't swing them on their fingers, or wear them on the backs of their heads as a joke.
The students who help you setup get to wear a white coat the whole class. (Don't tell the you got it from a delicatessen.) You select them on the basis of their other work. Completed written pre-labs, or their knowledge of the experiment to be done when verbally quizzed. Those kids you want to encourage to advance. As it stands, your original post is just going to give ammunition to the slacker kids who want to fool around even worse than not wearing safety glasses for the M&M experiment.
OK, in the case of Labcoats, I work in the Med, trust me, the last thing they want to do when it's 40 degrees (100+ for those that still think in Farenheight) is wear labcoats! If they're needed, they wear them, they're also availabe if they want to.
But, with goggles, they're a novelty at first, but an uncomfortable novelty that soon wears off.
I don't buy the "slacker kids" argument either. I don't HAVE kids fooling around during practicals, they learn that lesson very early on. Besides, I think the "cry wolf" argument is more imprtant with those kids anyway. With younger kids, I stress WHY particular safety precautions are needed, that only works if you do it at the right time. By the time they're 12 we're having class discussions about what the safety should be rather than me just telling them. By Year 9 (12/13 year olds) I'm expecting them to tell me what safety precautions they're going to use before they're allowed to start.
On our GCSE (at 16) and A level (at 18) papers, pupils have questons on practical work, and they are expected to be able to give sensible and relevant safety precautions for the experiment for some of the marks. Irrelevent ones (like wearing safety glasses to handle M&Ms) would not get the mark. (Indeed, for this pracitcal, the correct answer would be "there are no real hazards").
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In the case of junior scientists - they don't have the experience to do a proper risk assessment. M&Ms and water may not have any known hazards, but other experiments might. At what level of danger is it appropriate to not wear safety goggles or coats? Who makes that determination? It's best to get young scientists in the habit of wearing PPE whenever they are in the lab, regardless of what they think the danger level is.
And, as mentioned elsewhere, in a real laboratory there typically isn't just your own experiment going on. You may not be doing anything hazardous but the person next to you or behind you might be. Shrapnel flies, fumes diffuse, acid sprays, and so on. So again, I think there's a good lesson for students to always wear PPE no matter what they are doing. It will pay back later on when putting on eye wear and lab coat becomes automatic.
I worked for 10 years in a real laboratory (a hospital microbiology lab) and there are different areas for different hazards, you certainly wouldn't be wearing safety glasses everywhere (A labcoat that doesn't leave the lab except for cleaning, yes, but again that's for specific reasons, in this case to prevent spread of organisms to outside the lab and to protect those you are working with fro contamination).
I don't want safety precautions in my lab to be "automatic", I want them to be considered and appropriate. I want them actually thinking about safety, and I train them for that from their first time in the lab at age 11, when the first lesson is lab safety and why. Part of that lesson is to wear safety goggles when heating anything, or using anything that is, or may be (given the limits if what they know), harmful. That doesn't apply to M&Ms and tap water.
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Everyone wears safety glasses in a lab at all times.
No, they don't, unless there is a reason to.
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Everyone wears safety glasses in a lab at all times.
No, they don't, unless there is a reason to.
@jasongnome
Can we assume you live in a country where there is little concern for litigation.
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Everyone wears safety glasses in a lab at all times.
No, they don't, unless there is a reason to.
@jasongnome
Can we assume you live in a country where there is little concern for litigation.
No-one is going to win a litigation case because somebody isn't wearing safety glasses to mix M&Ms with water.
Besides which, it is blatantly to say everyone wears safety glasses in a lab at all times. It depends on what is going on. My lab is also my classroom, many lessons have no practical component. I'm not going to make them wear goggles to work from a textbook. Only if there's an actual risk.
Goggles aren't even worn "at all times" in professional labs, hospital labs nor University labs, unless there's a specific reason to because of the nature of the lab.
By the way I'm from the UK but now work in an International school.
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Can we assume you live in a country where there is little concern for litigation.
You mean anywhere but the USA. Although stupid frivolous cases are getting more common in Europe these days as well.
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Can we assume you live in a country where there is little concern for litigation.
You mean anywhere but the USA. Although stupid frivolous cases are getting more common in Europe these days as well.
You wouldn't normally get cases that frivolous in Europe. Indeed, judges over here sometimes throw out frivolous cases very early in the proceedings as a waste of court time.
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No, they don't, unless there is a reason to.
.. and their reason to do so is because they are in a laboratory where unpredictable things can happen.... A still could explode, someone doing a different experiment to your could fall and splash you etc..
Would you not wear a hard hat or steel capped boots and high vis jacket on a building site if you decided the task at hand was not that hazardous? Of course you would - you are dressing for the environment NOT the procedure. Just because your current task is not that dangerous doesn't mean that someone else can't drop something off o roof onto you. It is good practice and pretty standard to ALWAYS wear safety specs in the lab. Any uni lab will enforce the 'safety specs must be worn at all times in the lab' rule whatever the reason you go into the lab for... there will even be racks of spare glasses for visitors. (Why should a visitor need glasses if they aren't doing a practical?)
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Goggles aren't even worn "at all times" in professional labs, hospital labs nor University labs, unless there's a specific reason to because of the nature of the lab.
Where I work (a professional labs), the safety plan calls for eye protection to be worn at all times when in any lab, regardless of what you're doing. That doesn't mean everyone does it, but it is the official rule. I wager most professional labs in the US have similar rules on paper (if nothing else, because of liability).
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In a professional and university setting for a wet lab in the USA, goggles are always worn any time you are in an area where wet work or hazardous work is done. Not "being done right now" or "only safe things are happening right now" but "always." I would hope hospitals do the same.
It is the right thing to do to instill students with the idea that if science is being done, protection should be worn. You prepare for unknown unknowns, as well as known knowns and known unknowns.
Case in point for your simple M&M lab: What if someone drops glassware (beaker? test tube?), it shatters, and glass particles get in someone's eye? Certainly a hazard anyone would agree is possible, even likely.
Please don't wave your 10 years in a medical lab at us like we are rookies, you came to this forum because its full of experienced professional or academic chemists, many with their own decades+ of lab time.
You started with a valid complaint about the ridiculous warnings on SDS sheets, but will not find support for tactical use of PPE around here.
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.. and their reason to do so is because they are in a laboratory where unpredictable things can happen.... A still could explode, someone doing a different experiment to your could fall and splash you etc..
There is nothing in my lab that could explode and there aren't any other experiments going on. I've already said that if there were that would be a reason to wear goggles. The safetly advice os for THIS practical, not other things that may or may not be happening.
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In a professional and university setting for a wet lab in the USA, goggles are always worn any time you are in an area where wet work or hazardous work is done. Not "being done right now" or "only safe things are happening right now" but "always." I would hope hospitals do the same.
It is the right thing to do to instill students with the idea that if science is being done, protection should be worn. You prepare for unknown unknowns, as well as known knowns and known unknowns.
Case in point for your simple M&M lab: What if someone drops glassware (beaker? test tube?), it shatters, and glass particles get in someone's eye? Certainly a hazard anyone would agree is possible, even likely.
There isn't any glassware involved...
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Let's clear some things up here, because answers here are making assumptions that just aren't right.
My lab is a high school lab, the students are in there for their lesson, there are NEVER two lessons in there at the same time. There would not ever be other students doing other experiments in there at the same time.
My complaint was about this particular experiment, there is no glassware or any chemicals involved. Just tap water and sweets, in a plastic petri dish.
It needn't even be carried out in a lab, this could be done in a normal classroom, or a kitchen or kids bedroom at home with or without supervision.
The safety instructions are for this experiment. If other things are going on around them that require goggles, then obviously they'd need to wear them, but my comments are about THIS practical (and others like it).
I think schools in general do a lot more labwork than schools in the US (or at least that's what I gather from talking to American friends and colleagues), for that reason we have more labs, and they're not just used for practical work. My lab is also my classroom, it would be totally impactical to make the students wear goggles every time they're in there. They also do theory ,essons in there, sit written tests and exams etc etc etc.
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I think there are valid arguments on both sides for whether PPE should be worn at all times in a school classroom situation, so I'll stay above the fray.
As for the OP's other main point, regarding the inflation in safety warnings in recent years, I couldn't agree more. I teach in a university environment (both large undergrad labs and advanced master's and doctoral students), and increasingly find that students 'can't see the wood for the trees' when carrying out a safety assessment. This means they don't necessarily realize which are the genuinely nasty chemicals, and which aren't so bad. Solvents are a real problem - many of them (DCM, Et2O etc.) have rather dramatic H-phrases relating to exposure. Students don't realize they will be fine if a few drops of DCM land on their hand, less so with conc H2SO4. And as the COSHH assessments get longer and longer, the students pay less and less attention to them.
I think, in short, a COSHH assessment is no substitute for an experienced chemist next to you at the bench, who can advise as to when you need to exercise extreme caution. Expecting students to operate at this level for all experiments muddies the water and is counter-productive. Safety assessments should be realistic and simple.
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My lab is a high school lab, the students are in there for their lesson, there are NEVER two lessons in there at the same time. There would not ever be other students doing other experiments in there at the same time.
My complaint was about this particular experiment, there is no glassware or any chemicals involved. Just tap water and sweets, in a plastic petri dish.
I think you're missing the point... they get into the HABIT of wearing them when in the lab so that they are NEVER unprotected in the lab in case of un explained and unpredictable accidents. I once saw a 2.5L bottle of solvent just break into 3 bits... it had sat safely on the bench for month as and suddenly, pop! it fell apart washing the whole bench with di chloromethane. OK - Safety glasses wouldn't protect from that, but my point is that in a dangerous environment where dangerous and unexpected events can and do happen you need to wear the goggles. Did you go to uni? You aren't aloud into the labs at all unless you are wearing goggles regardless of whether there are any experiments going on at all.
I agree about the labelling though... it should have some prospective (as I said in my first post when I agreed with you) - if everything has HAZARD!! written on it then how do they know what is really dangerous and what is mildly irritating.
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I think you're missing the point... they get into the HABIT of wearing them when in the lab so that they are NEVER unprotected in the lab in case of un explained and unpredictable accidents.
I DO understand that point, but my lab isn't that hazardous, learge bottles of solvent, as per your example, aren't stored on a bench in my lab, they're stored safely in a fire and shock proof locked cabinet in the preparation area (where students arent even allowed). Keeping a large botte of solvent on the open bench in the lab would be considered an unacceptable hazard in a school by itself.
It isn't even vaguely practicable for students to wear goggles ALL the time they're in the lab, and, as I stated, I don't WANT lab safety to be a "habit", I want it to be thought through and appropriate for the risks at that time. Clarkstill has very eloquently stated a major problem with students not identifying hazards properly in University and a part of that is this "safety should be a habit" approach, in my opinion.
It can lead to students being LESS safe when they really need to be safe.
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Unfortunately (or fortunately, depending on your view) this just isn't the way the world works. Professional labs in industry and government do not rely on case-by-case risk assessments by staff scientists when it comes to safety. There is usually a blanket precautionary safety policy/plan that assumes that labs are a dangerous environment where unexpected things can happen. Professional scientists can sometimes take offense at these policies, interpreting them as an unfounded assumption by the organization that the scientists are not smart enough to determine whether an activity is safe or not. Maybe its a valid complaint, but when you get down to it, it's not really what the organization is doing, and as has been said here already, unexpected things happen in a lab, so even good risk assessments only get you so far in preventing accidents anyway. Still, I know a lot of professional scientists rebel against these policies and don't comply.
There's a valid complaint to be made that over reliance on blanket policies teach younger scientists not to be aware or evaluate the potential dangers of what they are doing, leading to a culture of complacency and reliance on precautionary policies rather than personal vigilance to ensure safety. On the other hand, there's also a valid point to be made that a person can't anticipate every source of risk in a constantly shifting laboratory environment that usually has a lot of moving parts (literally and figuratively). I've been working in a professional lab for many years, and while I like to think I am at least generally aware of the dangers of what I'm doing, I'd be lying if I said that I stop and do an in depth risk analysis of every lab activity I plan, and nor do I go around and ask everyone else in the lab what they are doing or do a detailed risk analysis for potential collateral damage. I, and I assume most professional scientists, operate largely by intuition and experience. Which is great and usually works to my advantage, but let's be honest, experience can itself often lead to complacency... what's the old adage - confident, cocky, lazy, dead? Automatically putting on PPE when I get in the lab at least gives me basic protections against my own complacency, and leaves me free to deal with the more unusual hazards that go along with specialized experiments that I might be doing on any given day.
Ultimately there's no scientific answer to what is the right balance of the need to protect (often inexperienced) laboratory workers from unseen dangers and the burden and expense of training individuals, buying PPE, and enforcing safety policies. One thing is for sure though: organizations that have professional labs will likely continue to err on the side of precaution because of the legal and regulatory framework within which these organizations must operate. A cynic may rightly claim that the policies exist not to protect the health of scientists but rather the bottom lines of the organizations that employ them. That's a little TOO cynical for me, but it's almost certainly an important consideration in drafting and enforcing safety policies (in fact, a lot of safety policies are legally required by organizations like OSHA in the US, so blame the nanny state if that's your bag).
Getting back to the main point - whether or not you should enforce laboratory safety policies as a primary school educator I guess is up to you. If your goal as an educator is to just teach the science - you are probably right, no harm is likely to come to the students by doing this experiment without safety goggles. (There's no point in getting angry at companies that publish lab procedures, though - for them its a matter of liability, and of course they are going to remind you to wear safety gear, no matter how innocuous the procedure sounds. It costs nothing to publish a few lines about putting on safety goggles and protect yourself from ridiculous lawsuits.) But you are simply way off base when it comes to the realities of working in a professional laboratory environment. Like it or not, blanket safety policies are the norm, and if your goal as an educator is to prepare students to become professional scientists and integrate them into what it's like to work in an industry or government lab, then you may well consider the value of getting them used to the culture and environment of professional science in addition to teaching scientific principles.
A few years ago I helped my daughter do a science fair project (http://www.chemicalforums.com/index.php?topic=73931.0) at home. It was on browning of cookies. Certainly there are few "real hazards" involved that would necessitate PPE, at least none beyond what you encounter in daily food prep. (Interesting side point: why don't we wear goggles and lab coats for our more prevalent chemistry experiments in the home? I.e., cooking. On the other hand, I certainly wear safety goggles when charging my wet cell battery with acid at home. So at home I do case-by-case risk assessments). But we wore safety goggles anyway. Why? I told her it's because when you're doing a "real science" experiment, you always wear protection. I didn't even think about it. I guess that's a way of showing that, for good or ill, I've become accustomed to the culture of laboratory science to the extent that it's automatic, part of the uniform. On the other hand, she thought it was great fun to dress up like a scientist like daddy does every day. So, while you're doing all this whining and complaining about the injustice of having to wear goggles for an M&M experiment, you may consider that your students might actually like wearing the PPE or the way it conveys a sense of importance.
When I put my lab coat and safety goggles on at work, I admit to feeling like I'm gearing up to do something meaningful.
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<SNIPPED but read in full>
Getting back to the main point - whether or not you should enforce laboratory safety policies as a primary school educator I guess is up to you. If your goal as an educator is to just teach the science - you are probably right, no harm is likely to come to the students by doing this experiment without safety goggles. (There's no point in getting angry at companies that publish lab procedures, though - for them its a matter of liability, and of course they are going to remind you to wear safety gear, no matter how innocuous the procedure sounds. It costs nothing to publish a few lines about putting on safety goggles and protect yourself from ridiculous lawsuits.) But you are simply way off base when it comes to the realities of working in a professional laboratory environment. Like it or not, blanket safety policies are the norm, and if your goal as an educator is to prepare students to become professional scientists and integrate them into what it's like to work in an industry or government lab, then you may well consider the value of getting them used to the culture and environment of professional science in addition to teaching scientific principles.
I work in a secondary school, (11 to 18), not a primary school, and let's get something clear, I DO enforce lab safety, we do have some normal blanket rules which are drummed into then from their first time in the lab. Students aren't ever allowed in the lab unsupervised, eating and drinking is strictly banned etc etc etc.
I also know that in a professional lab some blanket policies are always in place, but they will be particular to that workplace and the work carried out in that lab. As I said, I worked in a hospital microbiology lab and we has some blanket rules, but we also had specific rules for different sections with different risks.
However, we teach the UK syllabus, and it's a course requirement that students are capable of assessing safety and using safety precautions relevant to the practical in the question. If they put safety down that's irrelevent they won't get the marks. It's essential that I teach to the syllabus in question. It is also common practice in UK Universities for students to carry out their own safety assessments before practical work. Yes, there are basic blanket rules as well, I haven't at any point said, or even suggested, that there aren't.
I'm sensing from this thread that there are very different attitudes to lab safety on the two sides of the Atlantic.
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I'm sensing from this thread that there are very different attitudes to lab safety on the two sides of the Atlantic.
I agreed with you totally about the labelling and the information on the SDSs, it is just the wearing of PPE that I do not. I would drum it into them at that age that goggles are a must in any lab due to unseen and unpredictable dangers... when they get to uni they will HAVE to wear them or get kicked out of lab anyway so it is good standard practice to just wear goggles at all times in the lab... all uni labs enforce this so why not prepare them for it early?
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I do think it's overkill to require goggles for certain things, including the M&M experiment. BUT! Not if they perform the experiment in the lab. The reasoning being that a lab is a place where more than one kind of experiment is usually taking place. For students, it's about getting them into the habit of following safety codes that exist to take into consideration a broad set of potential hazards. It may not make direct sense, but oftentimes the logic of certain workspaces requires that creativity and independent thought be a kind of enemy. This is not necessarily a bad thing, as anyone who has ever tried to learn or teach table saw skills can tell you.
That said, it's important to consider the possible negative safety outcomes caused by any safety measure. Goggles in an M&M lab? Probably very few, if any. In the labs at my university however, there is a requirement that all undergrads, no matter how advanced, wear goggles that form a seal around the eyes. No safety glasses, no matter the coverage. These glasses fog up rather fiercely. People can't see what they're doing. This well intentioned safety rule has allowed me to witness fourth year students working with hazardous chemicals and strong acids and bases who regularly pull their a couple of inches off their faces just to vent them, as they fan under their eyes with contaminated gloves. Because of the condensation, there's also a lot more face wiping than should be happening in a lab. I got around this by literally building a small fan into my goggles to vent them, but it's a dumb rule that fails to take basic human behavior into account and in the process makes the environment less safe.
Funny story: I was talking to a 1st year Chinese grad student who told me that in China (which is a big place, so I'm not going to pretend this is universal) he and his fellow student would get in trouble for showing up to lab without a lab coat. Goggles, on the other hand, were optional.
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Nice discussion here. I always feel uneasy when I enter a lab withoug goggles. I already had few "eye" stories:
a) glass flask with waste solvent exploded in my hood while I was working there
b) cool eye inflamation that ended with surgery (see the member photo galery for picture)
c) friend of mine washed sintered glass with piranha and then with acetone without water wash in between. It exploded into his face. He didnt have goggles. Luckily, his eye was not hurt
so Im pretty cautios abuout my eye.
So goggles for me. All the time. When Im teaching undergrad labs, its goggles all the time.
I understand that you teach for highschool kids but to be honest, when I recall what s#*$ we did in chemistry labs at highschool, I would never allow myself into the lab. Kids do stupid stuff you wouldnt even think of. So its better to be safe than sorry
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I do think that it goes a bit far sometimes. However, you should wear proper equipment for every experiment/demonstration, even if it uses safe chemicals. A good way of looking at it is that everything can be dangerous. That being said, it seems that people are overly scared. I'm often asked "Will this blow up?", which leads me to think that chemistry has a big false understanding. Not that many things blow up. I am well aware that there are great dangers in chemistry, however knowing what you get into and common sense makes all the difference.