You've seen these images.

Huge chemical clouds covering crowds of demonstrators.

Riot police firing off rounds and rounds of tear gas canisters, especially

in places like Hong Kong, where riot police have been violently clashing

with pro-democracy protesters since June 2019.

And they're using a lot of tear gas.

In fact, more than 10,000 canisters of tear gas have been fired off since

protests started in June 2019.

It's so much tear gas that health officials are warning of its effects,

especially as 88% of Hong Kong's population has been exposed to these

chemicals and 7.4

million people live there.

The Geneva Protocol of 1925 banned the use of tear gas during wartime

along with other chemical weapons.

But tear gas can be used in riot control situations.

If I created a map for you, of all the places where tear gas is used

today, the entire map would ding.

It's been used in Chile, France, Egypt and here in the United States, like

on the U.S.-Mexico border.

First of all, the tear gas is a very minor form of the tear gas itself.

It's very safe. And during the Ferguson, Missouri, protests in 2014, when

people took to the streets to protest the fatal police shooting of Michael

Brown, an 18-year-old unarmed black man.

But its use states far back in U.S.

history. Tear gas was used on what is remembered as Bloody Sunday on March

7th, 1965.

That's when state and local police attacked hundreds of civil rights

protesters marching from Selma to Montgomery, Alabama.

However, tear gas was deployed by U.S.

police forces many times in the decades before the events of Selma.

And on top of that, tear gas is only one of the many non-lethal weapons

that make up the growing industry.

There's also rubber bullets, water cannons, lasers, sticky foam.

All of this makes non-lethal weapons, a multi-billion dollar a year

industry. And with unrest around the globe intensifying, that industry is

expected to surge by a lot.

In 2016, the non-lethal weapons market was estimated at $6.32

billion. But by 2023, this industry could make nearly $12 billion in

revenue. In the last 10 years, tear gas and other crowd-control weapons

have become a lot more popular.

So, where does all this teargas come from?

It turns out a lot of that manufacturing is happening on U.S.

soil. So tear gas isn't really

a gas at all. It's more like a vapor, full of fine chemical dust.

It's actually a powder inside the canister.

And then when it explodes, it aerosolizes into the air.

Tear gas doesn't just cause eyes to water.

It causes a burning sensation, difficulty breathing, skin irritation and

chest pain. It's so painful you want to keep your eyes closed.

It makes people feel like they can't breathe, that they're suffocating.

Sometimes it can get into your mouth and through your stomach and causes

vomiting and things like that as well if you inhale a lot of it.

But 90% of the time, it's probably really just pain to the skin, the eyes,

the nose and the respiratory system.

As for what exactly is inside a canister of tear gas, that's harder to

answer. There is no regulation of how this weapon is manufactured or sold.

And so no one's required to produce this data or to inform the public

about even what chemical is there.

Manufacturers aren't saying, oh, we are putting this concentration of tear

gas, this many milligrams into a canister of this size.

They do not share that information.

Early forms of tear gas were first used at the end of the First World War.

The exact details of who fired the first shot of tear gas remains up for

debate. But most historians say the French fired tear gas grenades into

German trenches in August 1914 during the Battle of the Frontiers.

There was this idea that all kind of biological and chemical weapons after

these sort of atrocities of the First World War, that we should not be

using chemical, biological weapons as an offensive force.

There was a very strong push by most countries to have a ban on chemical

and biological weapons.

As this got debated and nuance, there was often the U.S.

and a few other countries often wanted this kind of exception for tear

gas. They wanted it to not be classified in the same way as these other

kinds of gases.

So, various international treaties, like the Geneva Protocol of 1925,

allowed countries to still manufacture tear gas.

World powers like Germany, France, Russia, Italy, the United Kingdom and

the United States wanted to keep the chemical warfare infrastructure after

investing tons of money in its development during World War One.

So there was a very entrepreneurial general named Amos Fries who ended up

becoming the head of the chemical warfare service in the United States,

and he really went on a mission to turn a number of different chemicals

into what was called from wartime to peacetime uses, and one of these was

what we now consider to be tear gas.

General Amos began what we know now as a PR campaign to showcase tear gas

as a humane alternative to bullets in the 1920s.

He kind of allied himself with lawyers and publicists in order to create a

public relations campaign to convince people that tear gas was the thing

that law enforcement and security officials needed.

In a special kit available for immediate use is a complete assortment of

gas munitions, including projectiles and grenades.

Tear gas was marketed as a near harmless alternative to lethal force.

The gas bomb is tossed in the window. He missed the window, but he still

tosses it in.

And as that message circulated newspapers in the U.S.,

more and more police forces wanted the product.

The pictures speak for themselves.

There becomes this kind of hey, over in Philadelphia, they're using it.

Or, like down in D.C.

they're using it. You guys should be too.

There becomes this way of everybody needing to get in on this new

technology that was going to work for law enforcement, for peace-keeping.

The commercialization of tear gas kickstarted with two of the first major

players, Federal Laboratories Inc.

in Pittsburgh, Pennsylvania, and the Lake Erie Chemical Company in

Cleveland, Ohio. Since then, the market has expanded and tear gas has

become the most widely used non-lethal weapon.

There are different kinds of tear gas.

But the most widely used form is CS.

And today, the United States is the biggest producer of CS tear gas.

Tear gas is mainly deployed in three different ways by grenade, by spray,

like aerosol or water cannon, or by projectile, like a cartridge launched

by a riot gun, which is the most common way it's used.

Out of all the non-lethal weapons used for crowd-control, tear gas is the

biggest money maker by far and a single canister sells for around $20.

Tear gas is seen more as a go-to heaven because one little canister

affects a large area people and it is less likely to cause any lasting

harm than other forms of weapon.

These chemical non-lethal weapons are expected to maintain that

popularity. As for who's making the most money off tear gas, the U.S.

is the largest developer, operator and exporter of non-lethal weapons.

U.S. companies just sort of dominate the market because it has greater

reach, because it has multiple companies.

But it's not necessarily that the U.S.

companies like much, much bigger.

Two of those big companies are in Pennsylvania.

According to Feigenbaum, the biggest company is Combined Systems Inc.

in Jamestown, Pennsylvania.

The other largest U.S.

manufacturer in Pennsylvania is NonLethal Technologies in Homer City.

And then there's Safariland in Jacksonville, Florida.

These three companies did not respond to CNBC repeated requests for

comment. When it comes to exporting and importing tear gas, it gets a

little complicated. So, the reason that you can't get much information

about tear gas being exported around the world is because it's not

considered military equipment.

You know, there are federal contracts that show that certain equipment is

sold to certain places.

But because tear gas is kind of operating at a level below that, it's not

being sold government-to-government, it's being sold privately from

corporations to law enforcement agencies.

Tear gas trade is largely unregulated by international standards.

The U.S. Department of Commerce regulates its trade of non-lethal weapons

through export licenses.

For example, U.S.

exports of tear gas and other law enforcement equipment to Hong Kong

requires a license.

The Commerce Department is also responsible for enforcing those licenses,

so U.S.-made tear gas cannot be shipped abroad without government

approval. However, it's not always that simple.

There's also buying that doesn't happen directly.

If a distributor has bought from Combined Systems Inc.

and then that distributor could distribute that product and that product

could then show up somewhere, it doesn't necessarily mean that Combined

Systems Inc. said yes, you can ship that product to this place.

So, because there 's not any kind of international regulation or standard

or trade oversight, we don't really know just because a weapon is in a

place necessarily how it got there.

Because of this, some activists have taken the backtracking the trade

process by taking photos of the used tear gas canisters lying on the

ground during a protest.

Those photos are shared over social media and have gotten a lot of

attention during recent protests and unrest around the world.

For example, months of protests rocked the Whitney Museum of American Art

in New York City as people learned that tear gas made by Florida-based

Safariland was reportedly used on migrants on the U.S.

border. And the CEO of Safariland, Warren Kanders, served on the board of

the museum as the vice chairman.

At least until July 2019, when he ultimately stepped down from the role

because of his connections to the tear gas manufacturer.

Amid the protests, part of the Whitney's biennial exhibit was a project

called Triplechaser, which is named after a tear gas canister that breaks

into three parts. We want to know where exactly this tear gas has gone.

We want to find ways to make that process more efficient.

Forensic Architecture developed a machine learning technology to track

tear gas canisters from protest sites back to the companies that made

them. We don't know where this tear gas has been sold until it's been

used. At the very bottom, at the kind of grassroots, is one image held

like this often to a camera by an activist.

I was able to find maybe a hundred, 150 photos, of the triplechaser

grenade online. That's not enough to train a classifier to then be

speculative. So, what we have to do is build synthetic training sets,

which we can then use to teach the classifier what's a triplechaser and

what isn't. Once you've done that, once you have the photos that either

your artificial intelligence or your human intelligence is bringing into

the office, connect back to a company.

Mapping tear gas canisters this way has showcased how some trade

relationships work between different countries.

Traditionally, manufacturers in France, Germany, Israel, the United

Kingdom and the United States have supplied the majority of the world's

crowd-control weapons.

More and more companies have sprung up all over the globe in recent years.

As of 2018, more than 50 countries had companies that produce

crowd-control weapons.

One big issue, many of the countries were non-lethal production has

expanded into have very weak export control systems and a lot of these

products come with little or no transparency at all.

This means places with poor human rights records can easily obtain

non-lethal weapons where they could be misused.

Right now, the Asia-Pacific region is home to the fastest growing market

for non-lethal weapons, including India, China, Australia and South Korea.

One of the biggest Chinese manufacturers is state owned, Norinco.

There's question about whether their safety protocols and their standards

are the same as the more Western and Latin American product, which are a

bit more regulated. This is of what's happening in Hong Kong is a lot of

the European and the U.S.

companies have pulled out or paused shipments.

China is coming in and filling those shipments.

The number of Chinese companies developing these weapons has grown from 28

in 2003 to more than 140 in 2014.

Brazil and the United Kingdom also have giant manufacturers of their own.

The newest player on the scene is Condor Non-lethal Technologies.

They are a Brazilian company, and so now they do a lot of the distribution

to Latin America.

Brazil certainly uses lots of tear gas.

As the tear gas industry goes global and crosses international borders,

that makes it harder to regulate.

Here's the thing that's interesting about the riot control business,

unlike how we normally think about the arms trade, which is big weapons,

big numbers.

The trade in riot control weapons, the amount of money we're talking about

is much, much smaller.

As the demand for non-lethal weapons has grown, so has the call for more

restraint and regulation.

But it's unclear where exactly those mandates will come from.

We also see more of these weapons being used in increasingly violent ways.

So there are deaths from the actual tear gas itself, mostly when it's used

excessively. But, the real significant number of deaths that we see these

days is direct trauma from the canisters, especially if they hit the head

or the neck or the delicate bones of the face.

That's like throwing like a heavy can of Coke out of a gun at somebody's

face. That will break bones and they will kill people.

Currently, there are several global conventions and agencies that attempt

to oversee the use of tear gas and other non-lethal weapons.

The Alliance for Torture-Free Trade, launched in 2017 with more than 60

countries from all over the world signed on to it.

It aims to prevent, restrict and end trade in goods intended for the use

of torture or capital punishment.

The United Nations also has guidance on when and how these weapons should

be used in its code of conduct for law enforcement officials and the

U.N.'s basic principles on the use of force and firearms by law

enforcement officials.

There's specific guidelines on when you can even use any force.

You can't even think about tear gas unless there is a need for use of

force, and when that force is used, it needs to be proportionate, it needs

to be limited and it needs to be controlled.

There's also the Chemical Weapons Convention, which was signed in 1993.

The convention bans countries from developing or acquiring chemical

weapons. Under the convention, riot control agents like tear gas cannot be

used as a method of warfare, but they can be used for domestic riot

control purposes.

The manufacturers themselves also offer guidelines as to how the product

should be used. That's also what allows the companies to not have

liability. So, when a company's product maims or kills somebody, they can

say well the officers didn't use it according to the correct protocol or

guidelines. Chemical irritants like tear gas remain the most use

crowd-control weapon.

But, new technologies could change that.

Among the newer technologies in non-lethal weapons are acoustic devices,

also known as sound cannons or sonic cannons.

They can emit painful, loud sounds and there are questions about their

safety in crowd control contexts.

My guess would be that we would not see more use of sound to replace gas

because it would come with that same problem.

It doesn't just affect the individual people, it affects anyone who is

around. The use of stun grenades and other devices meant to disorient

people is also on the rise.

These weapons create a loud explosion and/or a very bright flash of light.

But, poor regulation and almost no quality control has led to defective or

misfired stun grenades.

An entirely new and developing category is directed energy systems, also

known as the active denial or ADS.

These are electromagnetic heating devices that deliver very high frequency

millimeter wavelength electromagnetic rays that heat skin on contact and

cause a painful burning sensation.

However, they're still only in development and they haven't been used in

any real world protests yet.

As people around the world take to the streets in protest and riot police

attempt to take the streets back.

Crowd control weapons will continue to see demand and not just tear gas.

I think it's one of these, you know, philosophical, like, it always makes

me feel like I'm in moral philosophy 101 class where it's like, well,

would you rather I shot you in the face or I teargassed you and your

friends. Most people would choose the tear gas, but this is not a real

question. The real question should be, would you rather I listen to your

political demands and engaged you in deliberative Democratic debate or

would you rather I teargassed you.

Who Makes Money From Tear Gas?

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