All language subtitles for Modern.Marvels.S23E05.Power.Pressure.1080p.WEB-DL.DDP2.0.H264-BTN_track3_[eng]

- [Narrator] It's an
invisible force all around us.

In the air, and beneath the sea.

It can cut through metal
and tear a house down.

- It has a lot to
do with weather.

And particularly it has
a lot to do with wind.

- [Narrator] From a
nuclear explosion.

To blowing up a balloon.

You'll never feel pressure
the same way again.

This is Modern Marvels,
super power pressure.

[dramatic music]

Pressure is hard at
work all around us.

An invisible force that makes

things move faster,
change consistency.

Or raise and lower temperature.

Pressure is often hard to
see, but it can be measured.

Whether it's in liquids,
in solids, or in gases.

Pressure is registered in
pounds per square inch or PSI.

That's literally the weight

of one pound pressing
down on one square inch.

Add weight, and the
pressure goes up.

The water that comes from
your tap, that's about 35 PSI.

The water shooting out of a
fire hose, about 100 PSI.

[dramatic music]
[radio chatter]

[fire engine siren]

Nobody understands the power
of PSI like firefighters.

Engine 22 of the Danbury
Connecticut fire department

is a state-of-the art
mobile firefighting platform

designed to do one thing.

Generate flame killing
water pressure, lots of it.

Engines like these are
technological marvels.

Capable of delivering more
than 1200 gallons per minute,

via multiple hose connections.

That's because the
engine's internal pump

creates enormous pressure

that can push water
out at top speeds.

Engine 22 only
carries 500 gallons.

So these high pressure
hoses are going

to need more water, fast.

In most fires, that water
comes from a fire hydrant.

A five inch diameter supply hose

locks into the
town's water system.

The pressure is on and the
hose springs to attention.

But the municipal fire
hydrants are unpredictable,

delivering water at
varying pressures.

So the fire engine
itself juggles the

inflows and outflows,
keeping the pressure constant.

Tackling a fire
from a ladder truck

adds another layer
of complexity.

The engine has to
generate additional PSI

to compensate for its
height over the ground.

- Attention driver 24
waters on the way.

- [Narrator] It's like
pumping a thousand

gallons of high pressure water
up a steep hill every minute.

- You have big fire,
you need big water.

- [Narrator]
Firefighters can't handle

this volume of water by hand.

- We could unsheath all
the shingles off this roof.

You're putting a
thousand gallons of

water out at 80 pounds

per square inch,
that's a lot of force.

It's an awesome amount of power.

- [Narrator] Nothing
is more critical

to this high pressure offense
than a strong defense.

And it comes from a fire hose.

A flexible cylinder lined
with synthetic rubber.

- This is a rubber
extrusion machine.

We're making a tube liner.

So the rubber actually
works really well

in the fire hose

because it enables the
fire hose to dilate

and swell and stretch
under pressure.

It also obviously
provides sealant

for the water to transfer.

- [Narrator] All American
Hose in Western Pennsylvania

uses about two and a half tons

of synthetic rubber every day.

This liner will fit inside
a sturdy outside covering

made of tightly woven nylon.

The weaving machines
spins at a hundred rpms.

The weave is so tight,

the machine's output is
only two feet per minute.

After weaving each jacket is
manually inspected for any

defects that could
cause the hose to weaken

and burst under
firefighting pressures,

The jacket and rubber
liner come together

on this 100 foot long table.

- A fire hose is usually
made of three sections.

One is the inner rubber liner,

which we insert into
the inner jacket.

And then we take that inner
jacket liner assembly,

and we insert into
an outer jacket

That protects the hose
whenever it's under pressure.

It also protects it when
it's under fire condition.

- [Narrator] Pressure
seals the deal,

with an 80 PSI hot steam
treatment for 15 minutes.

The steam expands the hose

to operating size
for the first time.

And activates an adhesive

that binds the inner
layers together.

The steam heat and pressure

make the fire hose
even more rugged.

With the addition
of alloy couplings,

the fire hose is
almost finished.

But first it must endure a
proof test

where it's subjected to 800 PSI.

That's two times
greater than the maximum

that firefighters
will ever need.

Why?

Because pressure can
spike unexpectedly

when hoses are twisted,
crimped, or run over.

Some hoses undergo an
additional burst test.

Over 1200 PSI.

That's enough to
break them open,

but the way this hose
is designed to burst

along its seam,
it could handle even that.

- Pumped up the hose
to the first pressure.

And when the hose burst, we
wanted to burst long wise

so it's safe like a banana.

If it bursts in
the cross section,

then it can be a loose cannon.

Could have hose
flying all around.

- [Narrator] It takes more than
1200 PSI to burst this hose.

A key test of its ability to
withstand enormous pressure.

But even to those of
us not battling fires,

water pressure plays
an essential role.

When you turn on the
tap and water flows out,

it's thanks to water pressure.

But how does water pressure
work and why is it so reliable?

As a liquid, all water
naturally flows downhill,

picking up power and
pressure as it travels.

It's the same basic way
water gets to your house.

A water tower is simply
a large water reservoir

elevated to generate pressure

and propel water into
your kitchen sink.

- Water towers use the
most patient force I know,

and that's gravity.

All you have to do is rely
on the mass of water to push it

through the pipes

and for the most part,
you're in pretty good shape.

- [Narrator] Your
typical water tower

holds more than a
million gallons,

but it's height is its
most important feature,

for every two feet that water
is raised off the ground.

It contributes one
more pound of pressure

or PSI to the system.

A water tower must be
tall enough to push water

through a network of pipes

and into surrounding
homes and businesses.

Most cities aim to generate
pressure between 50 and 100 PSI.

Water towers are usually
taken out of service for

maintenance once a year.

This gives us a rare opportunity

to step inside its pressure
creating construction.

This tank is over
90 feet in diameter

and it can hold a million
and a half gallons.

- When the tank is full,

there would be 35 feet
of water above us.

- [Narrator] In Louden
County, Virginia,

Coldwell tanks constructed

the country's biggest
water tower site.

These two massive 3
million gallon towers

are half steel plate and
half reinforced concrete.

- The pedestal has a
diameter of 64 feet

and 12 inch thick walls
all the way around.

The pedestal height is
on the order of 110 feet,

including the dome that
is on top of the pedestal.

- [Narrator] The 500
ton tank is hoisted up

to the pedestals dome
and locked into position.

This 116 foot diameter tank
delivers 50 pounds of pressure

into the local water system.

Serving 15,000 households.

But what happens to
your water pressure

if you live in a building

that's taller than the
highest water tower?

That's a problem that
New York city first faced

more than a hundred years ago
when it began to grow taller.

There wasn't nearly enough

water pressure for
the top most floors.

the solution became an icon.

A water tank for every
building over 80 feet.

- Water tanks are old
school, but they still work.

- [Narrator] Water
tanks like these

are replaced every 25 years.

The job has to be completed
in less than a day.

A challenge American Pipe
and Tank is ready to take on.

- While this tank is empty,

this building has
no fire protection.

So it's pretty critical

that gets back online
as soon as possible.

- The team spends
the first two hours

dismantling the old water tank.

- Watch it!

Next, they assemble a barrel

large enough to supply
this nine story building.

5,000 gallons should do it.

First, the team erects
a circle of stays.

And then tightens them into
position by a series of hoops.

All of this while dangling more

than a hundred feet
over the pavement.

In New York City,

the majority of old and new
water tanks are made of wood.

- Wood is a great material
for an outdoor water tank.

Wood is a natural
product, it breathes.

It does very well outdoors.

When you actually look at
this tank from the top,

you will look down and you
will see a true circle,

perfectly milled, and installed
like a big jigsaw puzzle.

- [Narrator] Like
all water towers,

once completed the
tank will require

very little attention to do
its pressure generating job.

- The water tank is a very
maintenance free type system.

A small pump in the
basement fills the tank

and gravity just does the rest.

- [Narrator] While
New Yorkers are proud

of their rooftop water tanks,

some landmarks prefer to
keep them outta sight.

The Empire State
building's one of the first

skyscrapers to hide
its water on top.

So even if you don't see them,

water towers and rooftop
tanks are up there.

Providing constant water
and steady pressure.

But what happens when
pressure goes out of control?

Countless aspects of
our everyday lives

are under pressure.

We harness water
pressure and store

it high in the air
until we need it.

We bottle up air pressure
and hold it in aerosol cans.

It may be everywhere.

But pressure is not
always under our control

[explosions booming]

Explosions.

[explosions booming]

[dramatic music]

An explosion causes
rapid expansion,

which gives birth to an
unpredictable pressure wave

that can travel
over long distances.

But what's really going on here?

Imagine a pebble
dropping into a pond.

The ripples move out
at a steady pace.

An explosion is
something like this,

but in the open air
and not at all steady.

Shock waves from an explosion

can only move as fast
as the speed of sound.

So they bunch up and that's

what creates a wallop
packing pressure wave.

But pressurized gases
aren't always destructive.

On a much smaller scale,
we even bottle airs

explosive pressure and
enjoy it, bubble by bubble.

Avery's beverages has
been putting the pop

in soda pop for
more than a century.

- If you wanna see what 300
pounds of pressure is like,

I can open a valve here.

It's pretty loud though,
I'll warn you ahead of time.

- [Narrator] Rob Metz
is the mastermind

who keeps these decades
old machines running.

- We're an old fashioned
soda company and it's,

as you can see handmade.

And we still make our soda
the way it was done years ago.

- [Narrator] That
means first making

a batch of flavored syrup

and then adding the other
half of the recipe, the fizz.

The bubbles in a soft drink
are carbon dioxide or CO2.

That's why we call the process

of putting the bubbles
in carbonation.

Pressure plays a
role in every step.

Avery stores their
CO2 in a liquid state,

under three hundred
pounds of pressure

at 40 degrees below zero.

- This is where we
control the amount

of pressure going
into the carbonator.

And this is where we adjust it

for the different flavors
for fruity flavor,

we're gonna have
it running around

60 pounds per square inch,

for a higher carbonated mixer
or a Cola, a ginger ale,

or we're about 80
pounds per square inch.

- [Narrator] Higher
pressure means more bubbles.

And you heard right,

colas contain more bubbles
than fruit flavored sodas.

That's simply because
we like our colas

much fizzier than other
carbonated beverages.

So how does CO2 find
its way into water?

- Coming in the, in the
top here is our water line

and in the side here is where
our carbon dioxide comes.

- Normally you can't see the
moment when the fizz goes in.

Here inside the carbonator

pressurized carbon dioxide
is forced into the water.

And a unique reaction occurs
between the water and the gas.

- Carbon dioxide is special

because it dissolves
in the water.

You can get a lot more CO2
into a bottle like this one

than you can nitrogen or oxygen.

And that's because the
CO2 is more soluble.

- [Narrator] By
the time it's done,

this water will
have absorbed three

times its own volume
in carbon dioxide.

That's a lot of gas.

And the higher the
pressure, the faster

the gas dissolves
into the water.

The soda finally comes together
at the bottling station.

Where the flavored
syrup gets dispensed

and mixed with the carbonated
water under pressure.

Then the capper seals it
off and traps the CO2.

- When they get down here,

the syrup and the carbonated
water aren't mixed.

So every bottle's gonna be

inverted three times
one, two, three,

and then they're
mixed to stay mixed.

So that's what's
happening over here.

- [Narrator] Now it's time
to sit back and enjoy.

Just don't shake things up.

Soda pop is by no
means the only beverage

in which we find CO2 bubbles.

A celebratory champagne pop?

Tthat's the result of
CO2 escaping the bottle,

Shake the champagne
and you excite the gas,

creating a surge of
bubbles and pressure.

Even agitated, much
of the CO2 remains.

There's still plenty
of fizz to be enjoyed.

But what if nearly
every single CO2 bubble

in a bottle is forced
out all at once?

We don't know if history
records the first person

who ever tried this,
but whoever it is,

they ought to get the
Nobel prize for fun.

It's what you're seeing here.

The ultimate example of
homemade explosive pressure.

It's now the infamous
Coke Mentos experiment.

A roll of candy is dropped
into a bottle of Cola

and the pressure release
is downright explosive.

How does it work?

Most scientists believe
that the unusual surface

of the candy spurs a
rapid chain reaction

of bubble formation in
which each new bubble

creates even more bubbles

and an instant release
of all the pressure

until the bottle is outta gas.

So the explosive froth
is all the carbon dioxide

leaving the bottle at once.

[upbeat music]

Like an explosion,
there's lots of pressure,

but it's released at
a much slower rate.

No pressure wave, no damage.

Just one big mess.

Pressure kicks off
many of our days.

It's the driving force
behind another foamy mess.

Only when this one blows
up, you put it on your face.

When Barbasol was
invented in 1919,

it was the world's
first shaving cream.

But it didn't become
the fluffy stuff

we know today until the 1950s.

With the advent of the
pressurized aerosol can.

Before shaving cream, men
had to lather up with soap.

Shaving methods have
evolved since then,

but the materials, not so much.

A visit to a Barbasol
plant in Ohio

reveals that shaving
cream still share

a key ingredient with
soap, steric acid.

It starts as flakes,

but it slowly
transforms into a liquid

as it heats to 150 degrees.

Emulsifiers, sudsing
agents, and filtered water

are combined with steric acid

in massive 3000
gallon mixing tanks.

The pressure is yet to come.

Over 10,000 empty cans enter
the production line every hour.

A 12 head filler processes
180 of them a minute.

- Well the shaving
cream at this stage

pretty much looks like, I
would compare it to skim milk.

Fairly watery and cloudy.

It's not until the
propellant goes into can

that it gets the
foamy rich texture.

- [Narrator] Once valves are
crimped to the top of each can,

they're ready to
receive pressure.

But for that step,

the entire production
line makes a detour

out of the factory building.

The pressure is
injected in a gas house.

That's separate
from the factory.

Barbasol uses two gases

as propellants,
propane and isobutane.

Both are potentially explosive,

which is why this process is
done outside the factory walls.

- So if there were
a spark present,

the roof would actually
get blown off the building

and this room would get
foamed to suppress the fire.

- [Narrator] The amount of
propellant in a single can

is not enough for a
consumer to worry about.

- Once the cans
leave this building,

they are under pressure.

- [Narrator] The cans return
to the factory under 80 PSI.

Then they run through a hot bath

to ensure that
there are no leaks.

The heat increases pressure

to over a hundred PSI,
simulating conditions

the cans might encounter
during shipping,

But how does shaving cream go

from the consistency
of skim milk to this?

You have to understand what's
going on inside the can.

The propellant gas is mixed
with a soapy solution.

Under pressure, they
become a single liquid.

When the valve opens
the pressure pushes

the liquid out and
foamy cream emerges.

- The material, the propellant,

is above its boiling
point at room temperature.

As a result, when
I open the valve,

I release the pressure
and the propellant boils.

That small amount of liquid
turns into a huge amount of gas.

And that's the way you're able
to get a large amount of foam

into a small can
of shaving cream.

- [Narrator] So inside
a can of shaving cream

pressure reveals what a
versatile force it can be.

But what if you need
a little more power

than the pressure
found in a can?

Once you start looking for it,

pressure is just
about everywhere.

From the common to the critical.

Plays a role in
nearly every job.

Cut something and it's
pressure that does the work.

It doesn't matter
what's in your hand

or what you're dividing.

[saw buzzing]

The best cutter in the world
employs blistering pressure.

Yet it's cutting with
nothing more than water.

It's a great demonstration

of the incredible power
of liquids under pressure.

But where does all
that force come from?

Jet Edge Water Jet Systems
has built a machine

that puts water under
massive pressure.

It's called,
appropriately enough,

a water intensifier system.

A hydraulic pump turns
at a hundred horsepower,

generating 3000 PSI.

This pressure is
transferred to a cylinder

that uses a piston
to put 75,000 pounds

of pressure on water.

If 75,000 pounds of
pressure per square inch

sounds like a lot, it is.

Consider this, nuclear
subs can't survive

deeper than 2,400
feet in the ocean

where the pressure is a little
more than a thousand PSI.

[upbeat music]

Water exits the
nozzle at mach two,

roughly 2000 miles an hour.

That's faster than a
bullet exits a gun.

A jet of pressurized water has

a lot in common with
another high tech tool.

- The ability to concentrate

this stream of water into
a into a very small area.

It's kind of like
using water as a laser

because that's what a laser
beam also does as well.

- [Narrator] The precision of

a water cutter is unparalleled.

The water jet blasts through
a sheet of carbon fiber

as if it were butter.

And it will do the same to
12 inch steel or titanium.

- First of all, the water
acts as a lubricant.

And second, it also
acts as a cooling agent

to take some of
that, that heat away.

- [Narrator] Unlike a water jet,

other cutting devices
generate heat,

Which can warp the material
or make it brittle.

A water jet is unstoppable.

In fact, if it weren't for a two

foot deep bath of
water underneath

the material being cut,

the water jet would be carving
holes in the factory floor.

- Water can cut a
number of things.

You can cut sheet
metal, foam, rubber,

but if you want to cut
something really thick,

like say six inches of titanium,

then you've gotta
add garnet abrasive.

And that is this
stuff right here.

- [Narrator] The abrasive
adds erosive power

to the pressurized water
and accelerates the cutting.

Water jet cutting has
been a boon to industries

like auto racing.

Michael Waltrip Racing
fields multiple teams

on the NASCAR circuit.

They build dozens of cars in

their North Carolina
facility every year.

Custom parts cut by
high pressure water

are used every step of the way.

Removing the engine
reveals all the parts

cut by the water jet.

- Here we have the bare chassis.

We can see a large
number of components

that we cut from the water jet

from our engine Mount here and,

and on the back of the engine.

Suspension pickup parts are
all cut from a water jet.

We've got steering arm braces

where the steering connects
is all cut on the water jet.

- [Narrator] The water
jet cutter shapes

the parts quickly
into an engineer's

precise specifications.

When you're traveling at
over 200 miles per hour,

where failure can be a
matter of life and death.

You wanna know that every
part works perfectly.

By machining parts flawlessly,

a water jet cutter
makes racing safer.

Pressurized water
is ideal for cutting

[water spraying]

and pressurized air
can be just as useful.

Although it lacks
the weight of water

air pressure can
turn into something

that will blow you away.

With a sandblast.

These machines clean
the toughest surfaces,

all powered by compressed air.

Nothing beats a sandblaster
its scouring paint

or grit and grime
from old parts.

And just like with a water jet,

the secret ingredient is
another gritty abrasive

that's driven by pressure.

- With pressurized media,

you don't have to go
anything over that.

I normally recommend 90
to a hundred for blasting.

When it gets fully decompressed,
that handle will drop.

And that tells you
you're ready to fill.

Now you're ready to fill.

- [Narrator] If a
100 PSI sand blaster

sounds lame compared
to the pressures

of a 75,000 PSI water
jet cutter, it's not.

At 100 PSI, a sand blaster

will strip naked
skin to the bone.

Bad boy, blasters manufactures
custom sand blasters,

and every single one
relies on pressurized air.

But blasting with abrasives
is a dirty dusty job

and can require
a lot of cleanup.

They've invented a vacuum
that sucks away the abrasives

and paint as fast as
it can be blasted.

The paint dust stays
in the air filter.

- Turn on the vacuum.

You see at the one 20 PSI,
this was running a 40-60 grit.

How nice of a, that's a
good, paintable surface.

- [Narrator] A
self-contained blast cabinet

made of welded sheet metal

makes sandblasting
even less messy.

Sand blasters are
highly efficient,

yet despite the name
they don't use sand.

Sand can cause silicosis, a
potentially fatal lung disease.

Most industrial sand
blasters like these

now use aluminum oxide.

The same material commonly
found on sandpaper.

Aluminum oxide can survive
multiple runs through a blaster.

- You can blast anything.

I got people doing anything
from blasting glass,

doing designs, metal parts, a
lot of aircraft industry work.

- It may not pack the
punch of a water jet,

but a blast of air
pressure is all it takes

to turn an old hunk of metal
into something shiny and new.

Pressure is everywhere.

Just look up

The atmosphere rises more
than 20 miles over our heads

and all that air has weight.

A very precise weight
in fact, 14.7 pounds.

That's how much is pressing
down on those of us

who live at sea level all
day and we hardly notice.

But there's something that
does get our attention.

Atmospheric pressure
lows and highs.

We know it as weather.

- Air pressure has a
lot to do with weather

and particularly it has
a lot to do with wind.

- [Narrator] Check
out any weather map.

The highs and lows
are air systems

seeking to equalize pressure.

Wind blows from areas
of high pressure

into those with low pressure.

- If you want to
think of it that way,

the more steep is the drop
off from high pressure

to low pressure, the more
severe is the weather.

- [Narrator] Up there,
it's a maelstrom

of varying pressures,
temperatures and humidities.

And in extreme cases,
it turns deadly.

But air doesn't exert
nearly as much pressure

as the other substance that
rings our planet, water.

30 feet of seawater
creates the same amount of

pressure as 20 miles of air.

Some of the most
destructive forces humans

must overcome are
in the deep sea.

At just 100 feet, water pressure

crushes an empty water bottle.

That's how much the air
inside it has compressed.

Of course you wouldn't be
seeing images like these at all

if it weren't for divers
with video cameras.

- We're under a lot of
pressure, time pressure,

water pressure,
to do a good job.

- [Narrator] Highly trained
underwater cameramen

like Bob Cranston put
their bodies on the line

every time they dive.

And the video gear they
take down with them

is worth tens of
thousands of dollars.

For divers, crushing
pressures are the enemy.

- And what we're feeling
when we go in the water

is the weight of the
water over our head.

The deeper we go, the
more pressure there is.

- [Narrator] Waterproofing
alone won't do it.

The only way you can
take a camera underwater

is using a pressure
resistant shell

called an underwater housing.

Gates's underwater
product designs

housing for all
types of cameras.

The process involves a
series of trade offs.

The shell needs to be big
enough to fit the camera

yet cylindrical in shape
to resist pressure.

The fewer, the parts, the
fewer things that can go wrong.

The main section of
the housing emerges

from a 65 and a half pound
block of solid aluminum.

Machines remove
88% of the metal.

Leaving a hollow
eight pound cylinder.

Then it's onto the tumbler,

which polishes away
any sharp edges

with synthetic rocks and water.

But even if all parts
are perfectly machined,

a seal can always fail
due to human error.

- The user has to do a,

a visual inspection to
make sure there is nothing

on the O ring that
can compromise it.

Something as small as say,

a human hair laying
across the O-ring

can allow water to
pass at that point.

- Large silicone O-ring seal
big openings against pressure

and tiny sleeves called glands,

employ a double set of seals

to maintain pressure
on the knobs and shafts

that control the camera.

As the last step before plunging
into the crushing ocean,

workers test the housing's
ability to survive.

First, they test
for normal pressure

by sucking all the air
out of the housing.

[machine whirring]

- Now we wait to see
if there's any changes

in the numbers on
the pressure gauge.

- [Narrator] If normal
air pressure can't find

its way into the
vacuum in the housing,

then it's ready for a much
more serious pressure test.

- The housing didn't
lose any pressure,

it's perfectly sealed.

- [Narrator] But how will it do

when the pressure is multiplied?

- So now I'm adding
pressure to the tank,

which will bring us up
to at least a hundred PFI

and simulate our dive
to about 225 feet.

[upbeat music]

- Thorough leak testing requires

putting every moving
part to the test.

- And looking for any water

that might be in
any control shaft

or around any sealing area.

And we'll actually torque
on some of the controls

to make sure that
we have nothing

in and around the control
glands themselves,

checking around the cord area.

This one passed the test.

[water splash]

- [Narrator] Down here,
minimal visibility

makes gathering images
even more challenging.

Gates camera
housings can perform

in waters as deep as 450 feet.

Where the pressure
is more than 215 PSI.

About 15 times greater
than it is on the surface.

Even at a hundred feet, the
PSI is four times greater

than at the surface.

A crushing force that also
challenges a diver's body.

- The ocean applies
pressure on all air spaces.

Our lungs have air inside
of it, our mask, our ears,

all of these areas have to
be equalized in our body.

Otherwise we feel squeeze and
pain and it's a bad thing.

- [Narrator] Even
the air coursing

through a diver's bloodstream
changes with the pressure.

This is one of diving's
greatest hazards.

Every minute, a diver
spends under water

his blood absorbs more
foreign gases like nitrogen.

If he ascends to the
surface too quickly,

dissolved nitrogen bubbles
will turn back into gas.

Just like CO2 in a bottle of
soda pop when it's uncapped.

This potentially lethal
phenomenon is called the bends.

Divers can use a computer
to calculate the amount of

pressure they're exposed to

and calibrate a slow
return to the surface.

Coming back from a deep dive

may take hours of
slow decompression.

So every diver
knows that pressure

is a force to be reckoned with.

Pressure is everywhere.

It's there when we need it.

But when it's outta control,
it can be brutally destructive.

It can be our worst
enemy under water,

but then we turn
around and use it

as the most powerful
tool in a factory.

Pressurized cans
throughout your home.

They not only
deliver foamy lather,

they can also dispense
some tasty treats.

Whipped cream
isn't the only food

that's created with
the help of pressure.

A kernel of corn pops when

the water within
it turns to steam.

Water expands 1600 times
when it becomes steam.

In an enclosed space,

that creates an incredible
amount of pressure.

The industrial revolution
changed our world,

but it can only happen after
we'd harnessed steam pressure.

So what happens if we
bottle up that steam

and put it to work
in our kitchens?

This place has almost
as much in common

with a science lab as a kitchen.

In fact, they call
it the cooking lab.

The team here researched
and photographed

a multi volume book
called modernist cuisine

to reveal the science
behind cooking

and to discover new techniques.

- We use high end technology
to play with our food

for the purpose of
making it more delicious.

More interesting.

- [Narrator] Pressure
is one of any kitchen's

most versatile tools.

Many homes have
pressure cookers,

but most of us take
them for granted,

rarely stopping to think
about how they work.

When you cook in an open
pot liquids can never get

any hotter than 212
degrees Fahrenheit.

The boiling point of water.

- The pressure cooker is a
fascinating piece of equipment

because it allows us to cook
in a high pressure environment.

We increase the pressure
to 15 PSI, one bar,

and that's an extremely
pressurized environment.

- [Narrator] The pressure is
now twice as great as normal,

it's equivalent to being
30 feet under water.

And what's strange is that
the water isn't boiling,

it will only do that when

the temperature
surpasses 250 degrees,

38 degrees higher
than the boiling

point at normal pressure.

That extra heat can brown meats

or caramelize vegetables faster.

- Increasing pressure
can speed up cooking,

create new flavors

and really facilitate the
cooking process in general.

- [Narrator] Pressure
cookers have been around

for more than a hundred years,

but they haven't always
had safety features.

Today, the lid is held in
place by heavy flanges,

a rubber gasket forms
a hermetic seal.

And if the pot over pressurizes,

a safety valve vents
the excess pressure.

- It will never explode.

It will just release all that
steam and it will be safe.

And now, it's very upset.

- [Narrator] Steam
pressure not only cooks,

it can also be put
to work sealing food

for long term storage.

- So this is a pressure canner.

Some of the features
are a little bit

different than a
traditional pressure cooker.

- [Narrator] A pressure canner

is basically a pressure
cooker on steroids.

It can withstand almost twice

as many PSI as a
pressure cooker.

Rather than a rubber gasket,

it has a metal to metal seal
that requires heavy clamps to

bolt it down and
hold it in place.

The pressure canner
also works double time.

It sterilizes jars
while sealing them.

The process of
heating and cooling

the jars leaves them with
a perfect vacuum seal.

These pressure canned tomatoes

can survive for
centuries on the shelf.

Another pressure
cooking technique

was perfected to send food
into space with astronauts.

It's the opposite of
cooking under pressure.

This is cooking in a vacuum.

Flavor, texture and
freshness are all preserved.

As water is drawn out under less

than a thousandth
of a pound of PSI.

[jauty music]

This is what's
called freeze drying.

- These carrots are very light.

Only one to 4% of
the water that was

already in them is still there.

It's so it's, it's
very, very, very dry.

- [Narrator] Once reconstituted,

these freeze dried
veggies look like

something you'd find in a cup
of dry noodle soup or ramen.

- So we're freeze drying,

we're manipulating
pressure to investigate

the future of cooking.

- [Narrator] Lightweight
dehydrated foods are perfect

for outer space.

Where every ounce of launch
cargo is carefully managed.

In fact, one dish
freeze dried ice cream,

was invented for NASA

and flew on an Apollo space
mission in the 1960s.

And it's all thanks
to the incredibly

versatile force
we call pressure.

We use it to build

and destroy.

To rescue,

to restore,

and to explore.

Wherever you go,
and whatever you do,

pressure will be
right there with you.

[upbeat music]