As chemistry teachers, our most important job is to make sure our students remain safe during our class.  Sure, we try to make sure that our students know how to balance equations and name compounds.  However, even if they never learn a single fact, it’s absolutely vital that every student walk out of our class in the same physical condition they entered it.

On this page:

  • Why a safe classroom is hard to develop
  • A new approach to lab safety
  • The guidelines for good lab safety
  • How to deal with dangerous situations when they occur

Why a safe classroom is hard to develop

Everybody agrees that it’s good to stay safe in class.  Students, parents, and teachers all want the students to stay healthy, and district-level administrators want to avoid lawsuits. Unfortunately, even though we’re all on the same page regarding what we want, there are several things that make this hard in practice:

Safety measures aren’t interesting.  If a school gets new football uniforms, everybody can agree that things have improved.  If a school gets new fume hoods, nobody will even notice.  Nor should they – while key safety equipment, fume hoods are extremely boring. It’s hard to convince funding people to spend money on boring things, no matter how important.

If it ain’t broke…  Your school probably hasn’t had anybody blinded lately.  You probably also haven’t had any students burst into flames or die from lead poisoning.  Unfortunately, when safety is implemented correctly, there is the tendency to believe that everything is just fine.  It’s not until there’s an accident that they learn otherwise.

Students don’t know what they’re doing.  This isn’t to say that they’re not smart, but rather to indicate that they have absolutely zero experience in a lab environment.  They don’t know how to work with glassware, they don’t know how to handle chemicals, and they don’t know how to conduct themselves in the lab.  These are things that can only be gained through hands-on experience, and our lab is where they will get this experience.

A new approach to lab safety

The typical approach to teaching lab safety involves giving students a great big list of rules and telling them to commit these rules to memory.  Though it allows us to say that we’ve taught our students about what is right and wrong, it doesn’t actually teach anything.

Instead of teaching rules, our goal should be to teach broad concepts.  Instead of giving rules for everything, a bit of guidance followed by trust in our students’ common sense will be a lot more effective.  I’m not saying that the rules should be ignored – they shouldn’t. However, I am saying that the rules aren’t enough to properly teach safety.

The guidelines for good lab safety

If you want your students to be safe in the lab, teach them these guidelines.  I realize, of course, that you will have to give them a big list of rules anyway because the school requires it. However, these guidelines, when followed by the students, will lead to greater safety.

Rule 1:  Always wear proper safety equipment.

Goggles must always be worn, without exception.  Even for labs without eye damage worries, goggles must be worn so that students are always in the habit of doing so. Furthermore, if you don’t wear your goggles when prepping labs, you need to make sure that you also wear your goggles.

On the other hand, gloves and aprons should not be worn in the lab.  Though gloves will keep chemicals off of one’s hands, most chemicals that are in a first-year chemistry class can be taken care of with soap and water.  Furthermore, gloves will melt to the skin if students touch something hot, making them a safety hazard in and of themselves.  Aprons mainly serve to catch fire when students lean over burners.  Either way, stick to goggles.

Rule 2:  Don’t do dumb stuff.

Students know what constitutes dumb stuff.  If they set their pencil on fire, add four times the amount of reagent to the flask, wrestle with one another, eat sandwiches in lab, or poke each other with syringes, they don’t need a teacher to tell them that they’re acting like idiots.  The proof:  Whenever students do these things, they look over to see if you’re paying attention beforehand.

Rule 3:  Treat all chemicals as being toxic and flammable.

This guideline eliminates the need to tell students not to use fire around the chemicals or to eat in lab.  It also ensures that students will think about the possible consequences when working with the reagents in class.

Rule 4:  You are personally responsible for the safety of yourself and people around you.

Students outnumber teachers by 30:1 (or more).  As a result, it makes no sense at all to let the teacher take care of safety while the vast number of people in class do whatever they want.  Put the kids in charge of safety and they’ll catch things that you’ll never see.

Rule 5:  Inform the teacher if there are unsafe conditions.

As in the preceding point, the students are better able to monitor lab conditions than you are.  If something is broken (or nearly so), they’ll be the ones who will let you know before it becomes a problem.

Rule 6:  Clean up after yourself.

This rule covers everything having to do with waste disposal, lab cleanup, broken glassware, and general tidiness.  Though it’s common to have separate rules for each of these, students know what constitutes a clean lab and what doesn’t, so working from this guideline should yield good results.

How to handle accidents in the lab

No matter how good your safety practices, there will be accidents in your lab that pose a danger to your students.  Because this is clearly a Very Bad Thing, it’s important that we know how to keep our students safe when this happens.

Preventing accidents

If you want to prevent accidents, you can’t just pretend as if they won’t ever happen. The following are steps you can take to keep accidents from happening in the first place:

  • Students must wear goggles.  Many chemicals that are harmless to the skin will fry eyeballs in a hurry, so it’s important that the eyes be protected.  Dilute acids, for example, will generally not cause problems to skin, so goggles can make major splashes into minor annoyances.
  • Students must be kept aware of specific dangers.  Though it’s important that students are always safe, it’s never a bad idea to tell them about dangers specific to the lab they’re doing.  This way, your students won’t waste their time worrying about reagent toxicity when working with acetic acid.
  • Students shouldn’t be afraid of screwing up.  If students are made to believe that they are incompetent and that they’re very close to killing themselves, they’ll be so scared in the lab that they don’t get anything worthwhile accomplished.  It’s good to teach caution to the kids, but it’s not good to teach fear.

What to do if there is an accident

Several times each year, all chemistry teachers can count on hearing a crash, followed by frantic calls of “Mrs. Smith!”  When this happens, you need to take instant control of the situation and make sure that everybody goes home in one piece.

In my experience, here’s how to do exactly that:

1.  Stop.  Stop walking, stop talking to students, stop grading, and stop whatever else you might be doing.  For five seconds, do nothing but look around and assess the situation in the classroom.  Though it may seem counterintuitive to initially do nothing when there’s a problem, you’ll find that you’ll more than make up for the lost time with your subsequent informed actions.

2.  Move toward the accident scene.  Don’t run, don’t call out, and don’t look agitated. When bad things happen you need to be in complete control of yourself so that your students will see that you’re in control of the situation.  Not only will this calm everybody down, but it will help to calm you down, too.

3.  Assess the situation with an open mind.  Just because your students are freaking out doesn’t mean that there’s something to freak out about.  A pipette full of alcohol may scare students if it’s squirted into a Bunsen burner even though it’s fairly harmless.  It might be that you’ve got a student who needs urgent medical care, but it’s more likely that the situation is already under control by the time you get there.

4.  Act to solve the problem.  The military has an expression when teaching recruits how to operate a rifle:  “Slow is smooth, smooth is fast.”  In other words, if you are deliberate in whatever actions you take, the problem will probably be resolved more quickly than if you thrash about.

Preventing future accidents

The only way to stop future laboratory accidents is to do a complete analysis where you assess responsibility for the incident.  OK… I’ve done this for you already:  You are completely responsible for this incident.  As the person in command of the class, you are the one who has been given the job of making sure that everything always works perfectly. Though it’s clearly not possible to actually do this in real life, the responsibility for everything in your class lies with you.  If you say otherwise, you will only make yourself look foolish.

That said, the fact that you’re responsible for this incident doesn’t mean that you’re a bad teacher, or that you did anything blameworthy.  However, as the person responsible for your class, it is your job to figure out what went wrong and take the appropriate steps to ensure it doesn’t happen again.

When doing your investigation of the incident, look for the following:

  • Something you’ve done:  Did you fail to tell the students something that could have prevented this?  Was your choice of lab appropriate for your students?  Though it’s hard to admit that you’ve screwed up, it’s vital to honestly assess this to prevent accidents in the future.
  • Something the students have done:  Did the students cause the problem by doing something that seemed reasonable to them?  Did the students cause the problem by screwing around?  Because the kids were the ones doing the lab, it makes perfect sense that something they did led to the accident.  If you focus on preventing problems rather than on assigning blame, you’ll find that students are far more likely to help you in your investigation.
  • Something wrong with the equipment:  Was gas released into the room due to a faulty fume hood?  Did a frayed wire lead to a fire?  These are easily fixed problems.
  • Sod’s law:  If anything can go wrong, it will do so at the worst possible time in the worst possible way.  Perhaps the accident occurred when a perfectly fine beaker decided to just break while being heated.  This sort of problem is completely unforeseeable and will inevitably occur.  The only solution to situations like this is to make sure that you and your students are prepared to handle things that go wrong.

Final words

Though this page may make it sound as if perfect safety is impossible to achieve, I want to let you know that perfect safety is not only impossible to achieve but also an unreasonable expectation.  By its nature, chemistry is a science in which dangerous things happen.

However, even though perfect safety is impossible to achieve, it is entirely possible to achieve a lab where the worst injuries that ever occur are cuts and the occasional minor burn.  This is our duty as teachers, and as those who care for kids.

This webpage and the related worksheets are licensed under the Creative Commons Attribution-NonCommerical-ShareAlike 4.0 International license (CC BY-NC 4.0).  For more information about this license and how it affects how you can use the contents of this site, click here.  This page was written by Ian Guch on December 2, 2014.  

Any links in the body of the text are not covered under this license and the copyright holders should be contacted directly for their terms of use.


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