Lab Techniques & Safety: Crash Course Chemistry #21

Lab Techniques & Safety: Crash Course Chemistry #21


Some of the best moments of my life have happened
in labs. Also some of the worst. Like the time that I took a week to prepare
a sample for NMR analysis, and then a classmate washed out the vials
while I was sleeping for the first time in 3 days. Because he “couldn’t find anything else” to
use for his experiment. Interestingly, that resulted in my personal
most significant laboratory injury. We all have one; I cut my hand while punching
a paper towel dispenser in frustration. No one ever brought it up again. Today, we’re going to talk about how to avoid
injury in the lab, and some good techniques for using laboratory
equipment correctly. First two lessons already learned: never wash out a vial you aren’t familiar
with and don’t punch paper towel dispensers. [Theme Music] Let’s start with some very basic safety stuff;
your hair. If your hair is long, it shall always be up
in the lab. If it is not, it will catch on fire.
I’ve seen it happen. It can also knock stuff over, and occlude
your vision, and droop into your flasks. Same thing goes for anything that might hang
off your body in the lab. Droopy clothing, especially sleeves, are a
total disaster. Clothes should cover your body as much as
possible; I like to go long-sleeve even. Never, ever, ever, ever, ever wear sandals
in a lab. Long pants, closed-toed shoes, and socks;
clothing that covers your entire torso. Always. I’m sure you look hunky in your muscle shirts, and I have nothing against exposed midriffs
as a principle, but not in the lab. Of course your eyes are your most vulnerable
organ. Always wear eye protection, and no, just glasses
do not count. And if you feel like your eyes are starting
to tingle, or hurt, or even if you don’t know how something might
have gotten in there, use the eye wash. Because it never hurts to be careful, and,
you know, we’ve all wondered what it feels like. I’ve actually never done this, so this will
be a new experience for me. Aaagh. Gah! It does not feel particularly pleasant,
but it’s better than having your eyes burned out. Do not eat or drink in the lab. Despite our best efforts, stuff does sometimes
get where we don’t want it to be, and if it gets in your food, or you accidentally
pick up the wrong cup, that’s just a really embarrassing story for
your obituary. Also I would generally suggest avoiding working
alone in a lab, especially if you’re working with any machinery
or hazardous substances. But it will be up to you and your advisers
to make that decision when the time comes. You may have seen this little symbol before,
here. It’s the Hazardous Material or HazMat diamond,
and it’s got some useful information in it. Each little box is rated 0 to 4. Zero being “no big deal,” and four being HOLY MONKEY BE CAREFUL. Blue is for health, the red is for flammability,
and yellow is for chemical reactivity. A 4 in health means certain kinds of exposure
will kill you. A 4 in fire is both very flammable and gaseous, so impossible to control outside of a closed container. And a 4 in reactivity means that it is capable
of exploding at room temperature. The little area underneath is for any extra
information like if it’s radioactive, or reacts violently with water or something. If you ever need to know more about a chemical
and what it might do to you or to the world, there is the good ‘ole MSDS, the material
safety data sheet. Every chemical has one, and it’ll tell you
all the terrible things that it might do to you. If you ever need to find one really fast,
you don’t need to go to the cabinet anymore; you can just Google ‘MSDS HCl’ or whatever chemical you think is in the process of killing your friend. There will be information on how best to treat
the person who got exposed. Of course, you should have always read the
MSDS before you even touch a chemical. Also, you should probably assume that every
liquid in a lab that is not water is flammable. This baby here is a fume hood. It sucks all the air in there out, so you don’t have to breathe whatever is going on in there. It’s also why it’s impossible to keep chemistry
labs at the proper temperature, because the A/C units and heating units are
constantly pumping in controlled air, and these are constantly sucking it out. So if you’re doing some chemistry that might
contain some noxious fumes, that goes on in here. And if you want it to work properly, first
you gotta turn it in. That’s the vent and that’s the blower.
Now it is sucking air. The second thing you want to do is make sure
the sash is at the right level. This has a little thing that tells you where
the sash is supposed to go. If you go above that, on this model,
[machine buzzes] it’ll buzz at you. If the sash is higher than that, it’s not
gonna properly vent all the stuff to the outside; some of it might get into your face and that
would be bad. As a side note here, if something happens
to you in the lab and if you don’t know whether it was serious or minor; you’re not sure, just tell your instructor. I once inhaled a bit of nitric oxide which, though initially extremely unpleasant, seemed to subside after a while. But it can have longer term effects: headache, nausea, disorientation, dizziness, pulmonary edema, death. So I’m glad I fessed up, so that I could get
taken care of. Speaking of, if you want to know what something
smells like, do not stick your face in it. Waft, waft it toward your face. Also never test something by tasting it, obviously.
And never pipette by mouth. I hear people say that and like who would, but then I just found out that Heiko, the
chemistry consultant for Crash Course, has twice gotten HCl in his mouth by-from pipetting by mouth, which I will never forgive you for. That is what these things are for. You put that on the end there, and then you
go one; you draw the liquid up with this thing. That’s what that’s for! Also, these days, most pipetting is done by these guys, which are way cooler anyway. Pipetting is one way to move a substance from one container to another, and it’s a pretty good one. But if you want to pour, you can pour, but
let me just give you a tip: commit. We tend to get all nervous when pouring stuff in the chemistry lab and go all slow with it, but that’s terrible; you won’t overcome the surface tension and it’ll dribble down the side of the container, so just commit! At the beginning and at the end.
Destroy that surface tension! OK, back to safety. The most common lab injuries are cuts and
punctures, and the most common source of those is cleaning up broken glass, which you should not do with your hands, but with a broom and a dustpan, and then deposit
the results into a bin specifically for sharp stuff. But the worst thing, and it has happened so
many times and it’s so terrible, is forcing a glass rod, or thermometer, or
a piece of tubing through a stopper and then it breaks and then right into and
through your hand. And it’s — you’re in the hospital and you’re
in pain for the rest of your life, probably. So when you’re doing this, and it is sometimes
necessary, you can use a bit of water or lubricant or some kind of Vaseline to make it easier to go through, and then you hold it close and make sure your
hand is not on the other side. So very close to make it go through like that;
not like this, ’cause that’s…no. When you’re done with an experiment, do not
just dump the results into the sink, unless this has been explicitly approved by
the person in charge of chemical safety. For some chemicals, like common acids or bases,
dilution is the solution to pollution. When they get diluted, all that’s left is
common ions like chloride ions from HCl or sodium ions from sodium hydroxide, in addition to some protons or hydroxide ions
that are neutralized by buffer ions that are present in your sewage system anyway. Bottom line is they can be flushed with lots
of water. For other chemicals, flushing is not a good
idea. It probably won’t hurt you, but it might hurt
the environment. Do put the products into an appropriate waste
container, but not just any waste container. Different solvents and reagents have to be
disposed of differently, and if you dump some stuff into the wrong
container, it can totally end up reacting with the other things that have been dumped in there. Not good. Rule of thumb: always know the right way to dispose of something before you even start to use it. This is an apron. It protects you and your clothes just a bit
extra in case you’re working with something hazardous
like concentrated acids. Aprons are nice because they’re easy to get
off if you spill something on them, while if you’re wearing pants, you might hesitate
a bit too long before you ditch ’em. Which reminds me: if you spill more than just
a bit of anything super bad on your pants, modesty goes out the window; just take them
off. Also, while you’re taking them off, you might
want to run over to this guy here. His job is to dump a gigantic amount of water
on you really fast. Now usually you don’t get to see these things
in action unless there is an actual emergency, but to thank you for sticking with us through this somewhat disjointed lecture on safety in the lab… I’m gonna take this off.
That’s a lot of water! Aah! Thank you for watching this episode of Crash
Course Chemistry. If you were listening, you learned what to
wear in the lab, how to dispose of chemicals, how to avoid the most common accidents in
the laboratory, how to pour properly,
what the HazMat diamond is, what an MSDS is,
and how to use a fume hood. This episode was written by me, our editor
is Blake de Pastino. Our chemistry consultant is Dr. Heiko Langner
who is sitting right there laughing at me. This episode was filmed at the environmental
biogeochemistry lab at the University of Montana,
so thank you to them. It was filmed, edited, and directed by Nicholas
Jenkins, our script supervisor was Dr. Heiko Langner. Our sound designer is Michael Aranda, and
our graphics team is Thought Café.

100 Replies to “Lab Techniques & Safety: Crash Course Chemistry #21”

  1. Omg!! Senior authorities at my school here in India need to watch this. There is nothing like this in our or any school here

  2. Ugh, my college chemistry teacher is relying on hanks videos to teach us. I like hank an all, but I don’t like that he’s our teacher for a course we pay for.

  3. Dawg which safety class crash are you referring to? The one my cousin Carol Stojinski missed? Dawg rocko left his pants at home KT Stojinski is sorry too, we are just turds in your pool of poop. Dr says I need an "examination" dawg just bear with us

  4. One time we were heating up some chemicals in a lab and stupid me touched the vial with my ungloved hand so I got a little burnt.
    That's my lab injury story.

  5. BEST EPISODE EVER πŸ˜‚πŸ˜‚πŸ˜‚πŸ˜‚πŸ˜πŸ˜πŸ˜πŸ˜πŸ˜πŸ˜πŸ˜

  6. Got dichloromethane in my eye while working a construction remodel job. Burned very intensely. Washed out my eye with a garden hose for like 30 minutes.

  7. Look up the MSDS for water. It is very informative.

    Disclaimer: We are not responsible for any brain damage caused by the repetitive reading of "Not applicable" or any similar phrase.

  8. This really helped me for preparing for 8th grade chemistry, half of this i didn’t know.
    β€œ4 being(in a Alvin and the chipmunks voice) HOLY MONKEY BE CARFUL!!!!”

  9. 3:42 Wear googles Mr. Green! and probably throughout the video and when you do experiments (this video and all videos that involve experiments, not necessarily just Chemistry or science)

  10. "𝐓𝐇𝐀𝐓𝐒 π€π‹πŽπ“ πŽπ… 𝐖𝐀𝐓𝐄𝐑"

  11. Thank you for this video. I have a lab safety quiz in my Chemistry class tomorrow and I didnt know if I'd be able to remember all the info. This video broke things down for me and made it simple. Im much more confident now that I understand the rules.

  12. I use acid everyday in my shop (hydronium chloride) and dump it down the street and I tell you that where the water comes out the tube on the ground the grass is always luscious. Nature can handle anything you throw on it. Even acid.

  13. So some idiot tipped over an ethanol flask while i was heating some HCl over a bunsen burner, within about 2 feet of me.

  14. I've got nitric acid on my pants before because my lab partner accidentally knocked it on me, thankfully it didn't touch my skin :0

  15. One of the first things I noticed, was the restraint on the cylinder tanks… Each tank should be restrained individually. Just my safety professional opinion …. make your safety video, assuring all items in the background meet safety regulations! πŸ™‚

  16. Hey there internet,
    My chem teacher created chlorine as a by product of some experiment and I took it like a fume hood. My nose bled and I was sick for 2 days. Yay!!

  17. Super video, but you're going to want to hold that pipette much nearer the top before putting it in the pi-pump or it'll break and go through your hand. Wish I had a nickel for every student who cut themselves by doing it the wrong way almost immediately after being shown.

  18. I remember watching this a few years back and now as a chemistry major I still go back to this video every now and then to tell people about the broken pipette/rod type of injury. Thank you so much for making this. πŸ™‚
    Don't know if anyone is reading this, but here's another tip- never dilute concentrated aqueous acid by simply adding water to it! Instead, add water to your beaker (or whatever type of equipment you're using) first and THEN pipette the acid into it. Otherwise, the first few droplets of water might react and heat up very quickly and end up splashing and causing burns. Be safe and stay curious!

  19. I accidentally poured a bit of HCl on my hand in 7th grade. Luckily it was extremely diluted and all I felt was a little tingling burn like an ant bite and then I washed it off

  20. What happens when you get a tiny bit of 1M NaOH into your thumb because a needle puncture, but immediately 'push back' the blood out of the wound?

  21. 5:30
    My college doesn't have those.
    We have to use our mouths

    And yes.
    I did accidentally get something in there.

  22. Watching this while being sad because in my school we have amazing biology, physics and chemistry labs,but they are just there.All preference is given to theory.We just copy down experiments in our practical manual without actually doing them in the summer holidays

Leave a Reply

Your email address will not be published. Required fields are marked *