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Chemical Hazard Assessment and Risk Minimization
Dan Olsen, CHMM
Those who conduct chemical reactions or work with varied and numerous hazardous chemicals will find this colloquium particularly informative.
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Well, hello, everyone.
Environmental Health and Safety
and the Office of Research and Economic Development
would like to welcome you all
to today's Laboratory Safety Colloquium:
Hazard Assessment and Risk Minimization.
This series of colloquia is offered in recognition
of the commitment by faculty and staff
at the University of Nebraska-Lincoln
to assure a safe and healthy environment
for teaching and carrying out meaningful research.
Couple housekeeping things first.
I think you all got a handout.
There are three handouts.
One is a copy of the safe operating procedure
of the same title as the presentation,
one is a copy of our poster, globally harmonized system,
and one is a survey.
If you could please complete this survey at the end
and leave that on the table, it would be appreciated.
Dan has cards of his at the back table as well,
so if you decide you want to pick one of those up
feel free to do that at the end.
I will be passing around signup sheets,
please try and print,
and our speaker today is Dan Olsen,
which many of you know.
Dan is a certified hazardous materials
management specialist, CHMM,
currently working at UNL's Environmental Health
and Safety Department.
So, Dan, take it away.
(applause) Oh great, great.
Today we're gonna talk about Hazard Assessments
and Risk Minimazations,
a topic that is near and dear to my heart,
and I'm sure by the time we get done today
it will be just as near and dear to yours.
Yeah, bit of a laugh on that one.
Okay, well what about me?
Who in here ever raised pigs?
You raised pigs?
You raised pigs?
Do you still raise pigs?
Yeah, our family does.
Oh, your family does?
You glad for the experience that you got to have
when you had to raise pigs?
Scooping manure and flies, and sortin' hogs,
and when they get out you gotta get 'em back in, right?
That's what I did growing up.
Y'know I'm really glad I had the experience,
but I'm really glad I don't have to do it anymore, either.
So I grew up as a pig farmer,
I graduated from Iowa State University
with a degree in biochemistry.
My first real job
was with the Iowa Department of Natural Resources,
just as the new underground storage tank rules came out
back in the late '80s.
I also did emergency response there.
Well, I didn't have degrees in either of those areas,
so of course they sent me off to training,
and what I learned,
getting my emergency response training,
is that they were trying to scare us to death.
So we saw fires and explosions and spills of acids
and things like that,
and one of the things they kept trying to drill into
emergency responders is that
before you go into a situation
you gotta know what it is you're dealing with.
You gotta know what it's hazards are,
and you gotta know how to protect yourself.
So of course when I came to university,
every chemical I encountered picking up waste
was a new chemical, so guess what?
I spent a lot of time reading safety data sheets.
Just last week, I advised a researcher on colchicine.
I don't know, I've never heard of it before,
so I went to the safety data sheet.
Dan, you have to enunciate or talk louder.
Talk louder, okay, sorry.
Okay, so, I still read safety data sheets,
so I'm practicing what I preach.
So I started here in the university in 1990,
my first job was basically hazardous waste.
I've also done lab safety.
I've done water quality,
we're talking water discharges, not drinking water.
I've done air quality,
and of course I've done emergency response.
Today what we're gonna cover
is why this is important to you.
We're gonna talk about the concept of hazard,
We're gonna go through a couple of examples.
We're gonna talk about how to minimize risk,
again we're gonna go through examples of it.
We're gonna do a case study,
and then after all that
we're gonna draw some conclusions from the whole thing.
So this is what most people think of
when they think of hazard assessments and risk minimization.
They think someplace in there a miracle occurs,
and I try to tell people, it's a lot simpler than you think.
Don't overthink it, it's very straightforward.
Let's talk about the legal: why it's important to you.
This is all based on occupational health
and safety administration regulations,
so it's a federal and it's a state law,
so based on those laws
you have a responsibility in part to,
whoops, oh, two of 'em,
comply with the employer's safety and health rules,
report and hazards immediately to your supervisor.
Now it doesn't necessarily be just a hazard to you.
If your coworker Bob is doing something that's dangerous
and you tell Bob "hey, that's dangerous,"
and Bob says "hey, leave me alone,"
then you gotta talk to Bob's boss and say
"Bob is doing something dangerous."
You've gotta report any job-related illnesses
or injuries to your supervisor.
If you supervise others, you'll be responsible,
and this includes PIs who have graduate students,
they have this responsibility,
to provide training,
correct improper work practices,
so as a PI if you walk into a lab
and you've got somebody working in the lab,
working with something that's dangerous,
and they're not wearing their proper PPE,
you have a responsibility to say
"Sean, you gotta go put on the right PPE
"before you come into the lab."
Discipline employees as needed,
that's another thing you got.
Now let's talk about the practical side,
I just told you the legal side.
Let's talk about the practical side.
You wanna protect yourself,
you'd like to go home at night
in the same condition you came to the job in the morning.
I've had professors actually tell me
that "we're just careful with everything,"
and I thought, "really?"
So let's talk about two things
that we're careful with everything for.
Engine oil versus nitroglycerine.
Both are oily liquids, right?
Do they have the same hazards?
How dangerous is engine oil?
It gets combustible if you heat it up enough,
but is it really toxic?
If it's on the floor you could slip and fall down.
It's toxic if you eat it.
Well it can be, yes.
What about nitroglycerine?
Anybody know any hazrds of nitroglycerine?
Is it extremely shock sensitive?
Yeah, fantastically shock sensitive.
Matter of fact it's so shock sensitive
that in order for them to actually be able to use it
they have to mix it with clay,
that's where dynamite comes from.
Otherwise it's too shock sensitive to handle.
So they don't have the same hazard.
Do you want to work with engine oil in milliliter amounts?
I won't work for you.
How about a liter of nitroglycerine?
Would that scare you?
So whether you're aware of it or not,
you actually are assessing hazards,
but you're assessing hazards for the chemicals you know.
So what I'm saying,
and you're also minimizing risks,
so what I'm saying is let's apply this
to things you don't know about.
How do you get it done?
So this is what we're gonna talk about today.
So, we have to differentiate a couple terms here.
Hazard versus risk.
Hazards are innate to a chemical,
it doesn't matter whether it's toxicity,
Benzyne is a known human carcinogen.
It doesn't matter whether I have a milliter of benzyne,
or I have a liter of benzyne,
they are both the same carcinogens,
so they have the same hazard.
Come on, gotta do something.
Okay, there are two kind of hazards.
There are health hazards and physical hazards,
and we'll talk about both.
Risk depends on how likely the hazard is to cause harm.
So we talk about gasoline.
500 gallons of gasoline has much greater potential
to cause much greater risk than a gallon,
it can cause much greater harm.
So, again, let's talk about health hazards.
Now in order for something to be a health hazard,
somehow you have to be able to get exposed to it,
so, and I've got people in here who know the answer to this,
what are the routes of exposure?
(audience member talking)
[Audience Members] Skin.
You've got skin, that's one, so you got skin absorption.
You can inhale it, that's right.
Directly into the bloodstream.
Well, how would you do that,
how would you get it directly into your bloodstream?
It could be injected.
Okay and there's, let's see, there's one more.
You could eat it.
Now, I know people don't go around eating chemicals,
but if you don't wash your hands
after working with chemicals you can transfer the chemical
to your hand and eat it that way.
If it's a dust, you could breathe it in
and it could hit your mucus membranes and get caught up
and you might accidentally swallow it.
So we've gone through,
we've gone through all of those.
Of those four routes of exposure,
which one typically has the greatest hazard to it?
(audience members talking)
Wanna say it loud enough?
That's because your lungs are built
to exchange gases and vapors,
so anything you inhale can be taken by your body.
Your lungs are designed to do that,
also your lungs are very sensitive tissues.
You breathe in something that's corrosive,
a corrosive gas, and it's really gonna hurt your lungs.
So, lungs tend to be the greatest hazard.
What tends to be second?
And this is kinda debatable,
but I tend to think of ingestion
because your digestive track is designed to absorb things.
Some folks might say skin, and for me skin can be,
but your skin's designed to keep what's
on the outside of you outside of you,
and what's on the inside of you inside of you,
so it's intended to do that.
There are chemicals that will go right through your skin,
and if you run into 'em then you need to be really cautious.
And then of course you've got the ingestion,
we talked about that,
and then injection, again, that tends to be needle sticks,
it could be chemicals.
I knew of an incident where somebody was handling
a high-pressure hydraulic hose,
and he kinked it in his hand,
and the hose broke and he squirted hydraulic fluid
into his palm, that was an injection.
Come on, do something.
Now, what are the three states of matter?
It's an easy one.
I usually have somebody say plasma.
Anyway, we're not gonna talk about plasma.
Of those three states, which one,
say they're all equally hazardous,
which state would tend to pose the greatest hazard.
[Audience Members] Gas.
Yeah, it's gas.
If it's a cylinder that's leaking,
it's actually pushing gas into the air.
You've got convection currents in a room,
you got air handling systems that can move that gas places,
So typically, gases are the greatest hazard.
The next hazard would typically be a volatile liquid.
Now try to think of a toxic volatile liquid,
and I really couldn't come up with any.
But again, it'd be something like ether volatility,
so you open the container
and it's rapidly evaporating into the room.
And again, you can inhale it,
it can be transmitted throughout a building.
Solids, they can be hazards if they're finally ground
and they become airborne,
but for most of the area where we're working,
we're working in labs,
there isn't a lot of wind,
there's not a lot to get the thing airborne.
So that tends to be the least hazard
of the three states of matter.
Oh we already did that.
So here's a summary.
Exposure hazards, greatest to least are,
we got those, right?
gas, volatile liquid, non-volatile liquid, and a solid.
Okay, so again, I'm going through this
because for something to be a health hazard,
you gotta be able to get exposed to it.
So here are, these classes of health hazards,
this is all based on the globally harmonized system
passed by the United Nations,
adopted by the United States,
these are the classifications based on that system.
If you've had your chemical safety training,
you've read about all of these classes,
you gotta have a working idea
of what each of these things means, okay?
Because when you read it on a safety data sheet,
if you don't know what a sensitizer does,
then it doesn't mean anything to you.
Of those classes,
which do you think poses the greatest hazard?
Ah, you're afraid.
I would vote for acute toxicity,
primarily because if something's really, truly, toxic,
you get exposed to it, you're dead now.
Carcinogen, you get exposed to a carcinogen,
maybe you don't get cancer for 30 years.
But if you're dead today, you're dead today.
Second one I would typically list to be skin corrosion.
You get very strong corrosive material on your skin,
and you don't do something about it almost immediately,
you're gonna have a permanent scar,
or it could be worse
And I don't want you to discount the other toxicities,
the other hazards here, but for me it's like
getting a kind of a hierarchy in my head,
as to what things should really get my attention.
Skin irritation, if I see it I'm gonna pay attention to it,
but it's not gonna get my attention like it is
if I find out it's a highly toxic compound.
Any questions on this?
Here are the physical hazards,
again this is the globally harmonized system
of physical hazards,
so I'm not going to go into detail on them,
but again you should have a working definition
in your head as to what a flammable liquid is.
Of these physical hazard,
which one do you think is the greatest hazard?
What are you saying, Julie?
I said the one you listed first.
Oh, okay, I gave it away?
And for me it's explosives because
that's something that can hurt you at a distance,
and you're hurt now.
They're not gonna hurt you in five years,
they hurt you right now.
Other ones that are not listed as explosives,
but the nice thing about explosives
is we don't have that many of them on campus,
other things that can react basically like explosives
are some of your organic peroxides,
some of the self-reactive substances,
they can basically detonate as well.
Something else that tends to be pretty hazardous
are your pyrophorics, right?
Open the container, you got a fire.
The substances in contact with water
emit flammable gases,
I don't like that.
It used to be water-reactive, now it's got that title.
There are certain chemicals, sodium hydride,
spills out of a container, if the air is moist,
there's enough moisture there
for the sodium hydride to ignite.
You would typically think about sodium metal,
throw it some water, it buzzes around,
and then you get hydrogen gas and it ignites.
As you probably already know,
the hazards are more complicated than that.
For example, some chemicals are highly toxic,
and they're gonna be called acute toxins,
and other toxins are going to be just considered harmful
even though they're gonna be listed as acute toxins,
they're not nearly as dangerous as others.
So how do you know how dangerous something is in its class?
They divide them into categories, and let's see here,
you go to...
You go to the second page of the handout,
it begins right at the bottom of that page.
It begins at the bottom of the page with these categories.
So the very first one, explosives,
you go across there it says "unstable,"
and it goes divisions 1.1 through 1.6.
So which of those, do you think, is the most dangerous
of those categories?
Do you think it's unstable?
That's the most dangerous explosives category.
You can't ship those.
If you go to the next page,
then you go to the top section of classes of health hazards,
you've got acute, toxicity, oral, dermal, and inhalation.
And this shows categories one through four,
there's actually five so we're gonna have to update this.
But category one is basically fatal,
exposure can be fatal.
So if you're going through a safety data sheet
and you're running into category ones,
or you're running into, y'know, type A, or division 1.1,
you're dealing with the most dangerous chemical
in that class.
So an organic peroxide type A is really dangerous,
and organic peroxide type F,
there's very little danger there.
So again, when you're looking at a safety data sheet,
you can automatically begin to rank,
ranking hazards on the chemicals you're looking at.
In our office we decided let's help the campus
kind of see how we see things,
so we created something that we call exceptional hazards,
and they're actually listed there
on the bottom of page three.
So it's explosives, unstable to divisions 1.1 through 1.3,
basically they can just detonate.
Organic Peroxides, A through C, not very many on campus.
Any Pyrophoric, again, exposed to air it's gonna catch fire.
Substances in contact with water emit flammable gases,
self-reactives, and acute toxicity, category one.
As you'll notice, every category, or every class up there,
is a physical hazard, with the exception of acute toxicity.
That's because all of those things can hurt you
without you doing anything else to it.
Just getting exposed to it it can hurt you.
So we've talked about hazard assessment,
let's talk about risk minimization,
so I pulled this one down.
And hopefully when we get done,
risk minimization is a lot simpler than that.
So in general, this is the order of preference
for risk minimization.
So you got, don't use the chemical.
So instead of using the solvent stripper to clean the part,
use sandpaper, or bead blaster.
You substitute it with something less hazardous.
Instead of the chlorinated salt for cleaning,
you go with the high-flash aliphatic solvent,
much less toxic.
You isolate the chemical from people.
It's in another room, or it's inside of a machine
where you can't be exposed to it.
You add engineering controls such as safety barriers
or exhaust ventilation.
Fume hoods, one of the most valuable tools
you have in a laboratory.
You adopt safe work practices, training, supervision,
to minimize risks,
and, last but not least, but last, is PPE.
PPE is the last thing you use,
now when you're working in a lab
you're probably using multiple levels of this.
You're using a fume hood, and you're wearing PPE, right?
So these things don't work to the exclusion,
but you're always looking at how can I make it safe?
I'm always looking for can I do number one?
If I can't do number one, can I go to number two?
If I can't do that, can I go to number three?
So where do you find this information?
Safety data sheet.
That's from the globally harmonized system,
it used to be a material safety data sheet,
now it's a safety data sheet.
I just said that.
It's been in effect for the last couple of years,
so you're going to see safety data sheets
changing the format,
and if you buy new bottles,
you'll see that the format of the labeling on the bottles
is new and updated as well.
Now pesticides that are subject to the
Federal Insecticide, Fungicide, and Rodenticide Act,
they're not subject to OSHA labeling,
but if you look up a pesticide,
you can probably find a safety data sheet for it.
So here's an example safety data sheet,
that I start off with,
and it's water, right?
So you come down through there,
and it talks about it here,
and gets you that information there,
and it comes down, they've got the address,
and you've got the emergency phone numbers,
and then it starts in
with this hazard identification, right?
And then you read something like,
"this stuff will kill you."
Then you think, well these safety data sheets,
they're just so over-the-top,
they're not useful to me at all.
The situation is,
the person who put together that safety data sheet
doesn't know the context
of how you're going to use the chemical.
Are you going to use water in milliliter amounts,
or in a gallon amount?
Are you in a boat on the ocean?
Now if you're in a boat on the ocean
and your boat sinks, can water kill you?
Yes, it's the context.
So when I read safety data sheets and I see things like,
"you've gotta wear fully encapsulating suits,"
"use only intrinsically safe tools and equipment,"
what they're telling me is, "there's a hazard here."
Depending on how I'm going to use it,
I need to pay attention to these hazards,
I need to minimize it.
So, let's look at a particular safety data sheet,
this for hydrogen.
Without going, what's it's greatest hazard?
What do you think?
It's flammable. It's a category one flammable gas.
So then the question is, is it always flammable,
or is it just sometimes flammable?
Where do you get it?
Again, safety data sheet.
So you get in there, and from the safety data sheet
it says the lower explosive limit is 4%
and the upper is 75.
Sometimes they'll use lower and upper flammable range,
or flammable range is used.
Now, really important, this is 4 to 75% in air.
When I mean air, I'm not really meaning
the 78% nitrogen in the air, am I?
I'm really talking about the 21% oxygen in the air,
so keep that in mind.
So what does it mean?
It means that any place in that range,
between 4 and 75, hydrogen will burn.
So in theory, pure hydrogen won't burn.
You can't make it burn,
because it needs oxygen.
Now what I do, is when I'm encountering a new chemical,
and I'm trying to figure out how dangerous is this,
what I'll do is I'll go back to
something I'm pretty comfortable with.
So in this case I thought gasoline.
How does this compare to gasoline?
Well, gasoline has a flammable range of 1.4 to 7.6.
The range is much narrower than it is for hydrogen,
but 1.4% gasoline's pretty low,
so that's, but it just gives you an idea
so you can see how you can compare it to stuff.
That's how I do it.
Okay so what other hazards does it have?
Oh, come on, do something.
From the safety data sheet,
it says it's a gas under pressure and a simple asphyxiant.
Now again, that's one of those definitions,
you should know what that means.
What is it?
It just basically means that hydrogen can displace air,
and then you don't have enough oxygen to breathe,
and that can kill you.
Something else from the safety data sheet
is it's incompatibilities,
and I'm kinda cherry picking
'cuz I'm trying to show you how I'm,
it depends on the situation what information's important.
As we go along you'll see why it is I picked
this particular piece of information.
So it's incompatibilities, oxidizers.
Turn it toward the computer, Dan, it'll go.
So, how do we minimize the risks?
This is really gonna be dead simple.
For the gas under pressure,
we're gonna secure the cylinder.
What kind of thing is that?
Is that an engineering control?
Yeah, I'm strapping it to something.
So I've got a tool there to help me.
I'm gonna keep the valve cover on it when not in use.
Now that's an engineering control,
'cuz it's made to have the threads on it,
you have the cap put on it,
it's also a procedural thing,
I've gotta remember to put the cap on the cylinder.
I'm going to keep the cylinder closed when I'm not using it.
I'm going to make sure I use it in a well-ventilated area.
What about flammability?
I'm going to keep it away from sources of ignition.
It says that all over the place in the safety data sheet.
What can they be?
Flames, hot surfaces, equipment, sparks.
Let's talk about sparks a little more.
Where do you get sparks from?
You get, have you ever flipped on an electrical switch
in a dark room and sometimes
you'll see a little arc through there?
That's a spark.
Electrical motors, when they're spinning,
they've got bushings on 'em,
and typically when that's spinning around,
you're getting little arcs off those bushings in the motor.
You can have tools that spark.
Of course, you can have, also,
you can have sparks from static electricity.
So what is this?
(audience laughing and talking)
It's a bad day.
It's a bad day?
Yeah, it's a bad day.
That is the Hindenburg, the airship Hindenburg,
this was May, I think 1937.
Anybody know what they thought
was the likely source of why this happened?
Some people said there was a bomb on the airship
and it was detonated.
What they really think was the mostly likely cause
of this, of what's going on here, was a spark.
In doing my research, I thought, well okay, it's a spark.
People can detect about a one millijoule spark,
so you got static on you and you sense something,
about the weakest thing you can feel is one millijoule.
Thirty millijoules and it'll make you jump.
It's a hard static discharge.
Hydrogen will ignite at 0.02 millijoules for a spark,
so it needs almost nothing for it to begin to burn.
Now, is the Hindenburg, is it exploding, or is it burning?
[Audience Members] It's burning.
Go up here.
There's a whole bunch of hydrogen up here
that isn't on fire yet, is it?
The flames have gotta move forward,
they gotta burn through the,
the bags, the gas bags holding the hydrogen,
it's gotta release the hydrogen,
then the hydrogen's gotta come in contact with air,
and it's gonna burn.
It took about 30 seconds from the beginning of this fire,
until it actually consumed the Hindenburg.
So 30 seconds, that's not an explosion, that's a fire,
So now let's talk about a different chemical, oxygen.
It's a category one oxidizing gas.
There's only two categories.
Anyway, it's a category one oxidizing gas.
What does an oxidizer do?
Well this is what is important for us,
is that an oxidizer can initiate or enhance
the combustion of other materials.
That sounds kinda nice and gentle,
it's like teddy bear, puppy stuff, right?
It's also a gas in refresher.
Here's an example of oxygen-enhanced combustion.
The only way you get these things off the ground
is you need a whole lot of oxygen present somehow.
Either liquid oxygen or in a solid fuel propellant.
How do we minimize the risks?
It's a gas under pressure, secure it.
Valve cover on it when not in use.
Keep it away from combustible, oxidizable materials.
Things like organics, grease, oil, flammable gases.
Remember, it says it's incompatible with these things,
which means if you put 'em together,
something bad happens.
So let's review.
We've talked about the hazards of hydrogen and oxygen.
We've talked about how to minimize the risks.
All of this information came from the safety data sheet.
Everything I've just,
with the exception of the millijoules stuff,
all of the rest of this came from the safety data sheet.
Were any of these things we talked about,
were they complicated?
No they were really simple, weren't they?
So, assessing a hazard,
determining how you would minimize the risk,
is really a straightforward process.
So now let's apply this to a research project,
an actual thing that was being done and that happened.
The case study we're gonna use
is something that happened at the University of Hawaii.
If you've followed anything on the news about that,
you kinda know where this talk's going.
But I still think you're gonna be surprised
at some things you'll learn.
So here's the research project.
Goal: to study the synthesis of polyhydroxyalkonates
called PHAs, by this bacteria, who could say,
how do you say that first word?
[Audience Members] Cupriavidus.
[Audience Members] Cupriavidus.
I had it as C. necator.
And then my cohort decided to put in the whole first name.
For me it was just C. Necator,
because I knew it, I was safe there,
and then she had to add the first word.
It's like I can't say that.
But anyway, the process is for,
it's for bioplastics research.
This has been being done for a while,
so I'm not talking about something that's novel.
The bacteria in part needs an ice growth chamber,
it also needs a favorable environment
that includes somewhere in the neighborhood
of 70% hydrogen, 20% oxygen, and 10% CO2.
These are all together, right?
Where we're at right now, does anything raise a red flag?
That's the flammable range of hydrogen.
Yeah, and I'm mixing it with oxygen, aren't I?
So you would think, they shouldn't,
it said incompatible.
So how can people do research with this stuff
when the safety data sheet says incompatible?
Well obviously they're able to do it.
But does that mean that it doesn't have a hazard?
Does that mean it didn't create a new hazard?
See, we're gonna learn about that as we go forward.
Let's talk about research papers, just a little bit.
Research papers often do not include information
on chemical, physical, or biological hazards.
They'll just tell you how to do it.
Details on the sourcing or setup of equipment.
They just figure you know.
Details on the process or reaction hazards.
For example, there are research papers that won't tell you
that this reaction will give off a toxic gas.
You're just supposed to figure that one out.
And so it's up to the researcher to identify
these extra hazards and to minimize them.
So in this case, this bioplastics research,
this is the first reactor they use,
it's a batch reactor,
they put the bacteria on petri dishes inside this,
and then they see the pressure gauge right there,
then they take this over to cylinders of CO2
and they put some CO2 in it,
then they go over to their oxygen,
they put some oxygen in it,
and they use this pressure gauge to determine
how much they put in,
and then they go over to the cylinder of hydrogen,
and they put some hydrogen in it.
Then they take a sample of it,
right up in here,
to see what kind of mixture they got.
So they can write it down.
Everybody with me?
The problem with this batch process
is that once the gases are getting used up,
you're not putting anymore in,
so they've created a second process.
Now I don't want you too caught up in the design,
it's just the thing,
here it is, you've got your valve for gas sampling,
here's your reactor, that's where the bacteria're gonna be,
probably in some kind of growth media, right?
You've got nutrient solution, pressure gauge,
measure oxygen, you got your gas supply line, right?
So they're gonna be able to feed the gas mixture
to this reactor as the bacteria are
in there doing their thing.
So where do you get the gases from?
They created, they went out and bought,
a low pressure tank,
and then they took this tank,
and you can see the pressure gauge on it, right?
There's the pressure gauge,
that's where they add the gases,
and then of course once they get it all mixed up,
then they can take a sample to see what the mixture is,
and then they can hook it onto that reactor,
and then feed the gases into the reactor as they're needed.
Does this concern anybody?
That I've got 70% hydrogen and 20% oxygen in this cylinder?
We know that we've got a combustible atmosphere, am I right?
We've got enough oxygen, we've got enough hydrogen.
The question is, how could it get going?
How could something bad happen?
There isn't a light bulb inside,
there's not a switch inside, it's just the pressure gauge.
There are no obvious sources of ignition.
So how could something go wrong inside the cylinder?
Could that happen?
And if it does happen,
does the tank burn like the Hindenburg,
or does it do something else?
But how could you have it happen?
We've all done this,
you walked across the floor in the wintertime,
you touched something and you got a static discharge,
Or somebody touches you
and then you got the static discharge.
Somebody touching the tank could transfer it to the tank,
it could be on the tank
and somebody or something touching the tank
could have a discharge that way.
Now, were there any warnings about this?
Again, this is University of Hawaii.
The postdoc reported, of course this is after,
I think this might have been after the fact,
I don't think this was before,
but she might have been saying this before,
she reported getting shocked when she touched the tank.
A week before, when she was using the first setup,
that little batch system, remember?
She charged this little thing with gases,
or she was in the process of it,
she heard a crackling sound.
The pressure gauge jumped, and then it began to drop.
What do you think happened?
We had a reaction in there.
The hydrogen and the oxygen reacted, turned into water.
The investigation that occurred later
decided that the reason it didn't blow up
was that the gases really weren't mixed at the time,
so it burned through that reaction chamber
like it burned through the Hindenburg.
So here it is, the postdoc opened the vessel,
and she found the plates were singed and cracked,
and that there was a burnt odor.
Here's a near miss.
And she doesn't pay attention to the warning.
Again, research like this has been done for years.
On the second operation, she had done it ten times already.
So, she set up the second reactor, the 50 liter tank,
that was that green tank we were looking at,
so she set up to do her 11th reaction.
And this is what happened.
You can see there's the tank, right there.
These drawers that you see opened,
the blast wave bounced them open.
Here's a little different shot of the tank.
You can see how it blew apart.
The investigation, and the red is blood,
just so you know.
The researcher was kneeling next to the tank
when it went off,
and it is probably when she touched it that it went off.
Here's another picture of the lab.
They call this a biosafety cabinet,
but I think it's a fume hood.
But, again, you see all the drawers that are open?
Shattered that, didn't it?
The tank I think was down in this area.
Whoops, go back up.
Okay, that's a refrigerator, across the lab.
Part of the tank blew off of it
and went over and hit the refrigerator.
They estimated that it,
the force of the explosion was somewhere between
70 and 700 grams of TNT.
She lost part of one of her arms, the lower part of her arm,
and when I was reading the report,
they just said she lost it,
and I thought "well, didn't they try to reattach it?"
Well, when I read the investigation report,
they said there weren't any pieces big enough
that they could reattach, so she lost part of her arm in it.
Of course she also suffered burns,
but from my standpoint, she's really lucky to be alive.
That's where the tank was sitting on the floor.
So you can see the gouges, I suppose that's concrete.
Okay, here's a schematic that the investigators put together
to try to understand what exactly all happened in the lab.
So let's go around here, there she is,
there's the tank,
some of these red lines are saying,
"we found pieces of her arm in these other locations."
So let's go around here.
There's the, they call it the biosafety cabinet,
I'm saying the fume hood,
so it blew the side of it off,
it pushed it back into the wall,
that's what it shows there,
and it pushed that part of the wall out six inches.
It knocked over one of these tanks,
that was an oxygen tank, and it damaged the valve
and the oxygen tank bled into the room.
Nothing happened, it just bled into the room.
There's the refrigerator where it got hit,
and you can read this,
hits the wall, because of the pressure,
and it blows part of the drywall out into the hallway.
We got some other things that are impacted.
Over-pressure on the drawers, when I mentioned that before,
how it knocked the drawers open
with the pressure that hit 'em.
So, pretty serious stuff right?
Okay, this is the part where, it bothered me because,
I'm not omnipotent, so now we're saying in hindsight,
well that's like armchair quarterback, right?
Well if you're gonna learn something,
you have to say what could have been done different?
So you're kinda forced to go forward with this,
even though you might not be comfortable with it.
Could they have done that,
ground the tank to prevent static?
Couldn't hurt, right?
They found that the pressure gauge
was not intrinsically safe, but they found that that
was not the source of the explosion.
You could've filled and used the tank remotely.
Now, 70 grams of TNT, how remote do you wanna be?
That's pretty remote.
And that's a risk minimization practice, right?
So pretty difficult.
They could've designed a system that mixed the gases
as they were going into the reactor.
Now, I haven't looked at the reactor,
could the reactor have had static and blown up?
She could've heeded the warnings that she was getting,
she was getting a number of them.
Remember the near miss.
I've also thought about this.
Some of these considerations might not be obvious.
She's a microbiologist, she's not a compressed gas expert.
But that's the point, isn't it?
She was working outside of her area of expertise.
She could've called the gas company,
saying, "hey, I need help putting this together."
She could've called Environmental Health and Safety
and said, "it says these things are incompatible,
"but obviously people are putting them together,
"people are doing research with this,
"so am I missing something?"
There was an instance here not too long back,
few years back actually,
where we found out researchers were gonna be mixing
potassium permanganate, which is a strong oxidizer,
with liquid paraffin, which is organic,
and we were saying, "you can't do that,
So we read their research papers that they had,
the researchers had recognized that,
and they had actually evaluated that material
And then we took it beyond that to say
let's do what we can to this stuff.
We got with the state patrol,
we actually tried to detonate a little piece of it,
and it wouldn't detonate.
It would burn, but it wouldn't detonate.
And as a result they did their research.
Other ramifications, this is the University of Hawaii.
So, they were fined $115,500 by OSHA,
which doesn't sound like that much.
The explosion caused $716,000 to the lab building.
I believe the lab where the explosion occurred
is still shut down.
And this is, what, a year or two ago, I believe?
The building was closed for days.
I'm sure no researchers needed to do any research, right?
I'm sure they didn't have anything that was time sensitive,
like bacteria cultures and stuff like that
that they needed to change out, right?
Of course the university is being sued by the postdoc.
There is an official report, 38 pages long,
that made recommendations
for how to make the research safer.
The investigation found failures at all levels
from the research, to EHS, to administration.
Now, do you think that that 38 pages
are gonna affect the research that's done?
Hopefully it'll make it a lot safer, right?
But do you think it'll make it faster to do research
So here are the conclusions,
here are the things to take home from this.
When you're going to do something
that you haven't done before,
you've gotta go beyond the research papers.
You've gotta go into the safety data sheets.
You've gotta read other support information.
You've gotta consider the chemical reactions.
Again, she's mixing two chemicals that were in theory,
well, not in theory but WERE, incompatible.
So she went from oxidizer, inflammable gas, to explosive.
She changed the hazards.
Gotta consider equipment setup and process hazards.
Again, these two chemicals aren't a problem
until you put 'em together, right?
And then of course you've gotta,
when you're working outside your area of expertise
you gotta enlist the experts in that area.
And I know we're getting into a lot more
so you've gotta recognize that
if you're gonna be putting things together
that are not your area of expertise
you gotta find somebody to advise you on it.
If you call us, it may not be me.
It might be the fire marshal that I'm gonna get ahold of,
because he's the expert.
These near misses, and things like that,
you need to report them.
You can't learn from it unless you report it.
So if you've got a departmental safety chair, let them know.
You got just a chair of the department, let them know,
so that we can get it out to the department.
Chemistry, if they have a near miss,
there's an e-mail that goes out kind of
to the departmental folks to say "here was a near miss,
"this is what we should've done differently."
Also, this right here in this green box.
This is our webwite, this is the EHS homepage,
and you can't see it very well,
but it's a near miss reporting system,
so you can click on it, fill it out, and it'll come to us.
If we need to, and we almost always follow up on it.
This is something I didn't have in 1990.
We've got the world wide web.
You can jump out there, read a safety data sheet,
you can read a couple different safety data sheets.
You can go to Sigma-Aldrich,
and then you can go to Fisher,
if it's a fresh gas you can go to Matheson,
and read all these different safety data sheets.
You can read hydrogen oxygen mixture hazards,
and type it in, 'cuz you know it's something new.
There's a chemical safety library
that's been recently created.
I haven't had a chance to really look at it that much,
but it's being supported by a lot of chemical industries,
and it's a place where they're all going to put out
reaction hazards that they've encountered,
that are not normally necessarily published,
because the thing in Hawaii,
the reason we know about it's
because somebody got injured, right?
If they just had an explosion, man,
maybe we wouldn't have known.
But this way, they're trying to get it out
that "here were our near misses,
"here was an accident, this is how it happened."
There's also something called
Bretherik's Handbook of Reactive Chemical Hazards.
If you're determined enough, you can find this online.
'Cuz I found it.
You can look up chemicals,
you can search for chemicals in there,
for what kind of hazards they are.
It generally won't say you add hydrogen to oxygen
you get explosion, right?
It may not go to that detail,
but it can still at least give you some information
on chemical hazards.
Of course you can always call us,
and even if we're not the experts,
usually we can find somebody who is to advise you.
And of course we'll meet with anyone on any subjects.
Are there any questions or comments?
It's kind of a somber end to this discussion, so
I gotta have this.
Oh, gee whiz!
We got puppies and kittens.
So there's a happy ending.
If I could add a comment.
If you have a question we need to use this
so it's on the video.
My comment is,
is if you're working off of published material,
there's always a contact for the authors.
Yes, you're right.
Did everybody hear that?
You can always contact the authors
on how they set things up,
is that what you're saying Julie?
And what hazards that they had identified.
I doubt that they did that in this situation,
because other researchers are doing it,
somehow they managed to do it safely.
On something like this,
I don't know if I'd be comfortable
with just grounding the tank,
because of what the stuff is.
We're not talking a fire here,
we're talking a significant explosion.
We would've needed a whole lot of help
to say "okay, this is a safe thing to do."
We probably would've brought in the fire marshal,
compressed gas company, things like that,
experts to help advise us.
So good point, Julie.
I have a question about personal protection equipment,
how are they reliable and how can I maintain?
So the question is PPE, personal protective equipment?
How about reliability, usability, reliability?
It's getting better.
For example on a Sigma-Aldrich safety data sheet
for a chemical,
you can go back to like the PPE recommendations,
and they'll actually give you on at least
almost all the safety data sheets I've looked at,
they'll give you a specific glove to wear
that's supposed to be good against the chemical.
Now, guess what, almost all the time
it's a Sigma-Aldrich glove,
but at least they're telling you
something that will be there to protect you.
The other PPE it just depends on what you're working with.
If you're working with something,
let's say you're working with a lot of flammable liquids.
Well you might not wanna wear just a regular lab coat,
they make lab coats that are fire resistant.
It's the same thing with your safety glasses.
Safety glasses that are sold are required to meet
federal standards, and so that means if something,
so they know that if you get hit by something,
an object or whatever, that it's supposed
to be a certain amount of resistance to it.
And then of course you've got your standard clothing
you're supposed to wear.
Collars that are relatively high,
pants that go to the floor, closed-toed shoes,
not mesh-toed shoes closed-toed shoes,
but we're talking real closed-toed shoes, like leather,
and I've always advised people
if they're working with things that are flammable
or could catch fire or something like that,
maybe they oughta consider just wearing cotton or wool.
Stay away from the polyesters.
There was an incident at UCLA a number of years ago,
and the gal was working with a pyrophoric liquid,
and she got some on her,
and of course pyrophoric liquid, what's that mean?
It catches fire, right?
Well, she eventually died from it.
She was wearing a plastic, a polyester,
rayon type of sweater in the lab that day.
She didn't have a lab coat on,
she wasn't wearing safety glasses.
That fire that got on her then used her sweater to burn.
So she made things worse for her just by her clothing,
so PPE is really important.
In a lot of cases if you got the right PPE on
it'll help you a lot.
I've seen incidents where, there was a firefighter
and he wasn't wearing the right bunker gear.
He had a t-shirt on and he had the straps
for bunker gear pants,
so the straps are shoulder straps.
He got caught in a fire ball.
What was amazing to me was,
he had first and second degree burns
all over the place on his upper body,
but where the straps for the bunker gear went,
nice, white skin.
Because he had his PPE on.
So you get the right stuff and it's very effective.
Any other questions?
There was also a question,
part of the last question was about
washing lab coats?
Excuse me, washing?
Washing lab coats, can she wash lab coats?
What's our policy on that, Brenda?
Washing lab coats?
We don't have a policy on that.
Oh, we don't, okay.
There are certain care instructions
when you're dealing with flame-retardant,
there's other considerations there.
I said there is no policy,
but there are considerations if you're gonna launder,
particularly if you're gonna launder
flame-resistant protective gear,
there's certain instructions that need to be followed.
We would discourage laundering lab coats
that are known to be highly contaminated
like you were part of a spill,
but ordinary lab coats,
typically like in a bio lab,
that are just ordinary soiled, wouldn't have an issue.
So basically Brenda's saying,
depends on the level of hazard in the coat.
If you're willing to put it on, right?
Then aren't you willing to wash it?
Whereas if you don't wanna put it on, do you wanna wash it?
No, because it's too contaminated,
you don't wanna even put it on.
So that's kinda how I would carry that.
And it depends on department,
some units on campus they've got their own washer, dryers.
Some units on campus, if they want to,
they can go in with an exchange with a company,
and the company will take their lab coats
and bring them new lab coats.
Those are out there, and if you have questions on that,
you know we can talk about that after this if you'd like.
Any other questions?
The screen size you are trying to search captions on is too small!
You can always
jump over to MediaHub
and check it out there.
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Environmental Health & Safety
Laboratory Safety Colloquium
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