Inside Porton Down: Preparing For Gas Attacks

Sky News gets rare access to Porton Down, as scientists work to protect us from the threat of a chemical weapons attack.

Video: Alistair Bunkall straps on a mask before walking into the gas chamber

By Alistair Bunkall, Defence Correspondent

We are only allowed to film one building on the campus - the old white, almost colonial Headquarters.

 It was built in 1918, after World War One in reaction to the use of gas attacks by the German forces.
We can't film any other buildings, or corridors, or cars, or people's faces.
Because this is Porton Down, the home of the Defence Science and Technology Laboratories and they prefer to work in secret.
One hundred years on from the mustard and chlorine gas attacks on the trenches in northern France and Ypres Salient, I have been given rare access to this establishment, to see how technology has moved on.
"The range of threats we face in terms of their complexities is probably quite broad," Simon tells me.

Porton Down had a sinister reputation in the early part of the 20th century

For their own security, we're asked to only publish the scientists' first names.
Simon is the Division Head of Biological and Chemical and Radiological Sciences.
"I think it is fair to say that if you look at the press and you watch the news then you can see that it's been a very unstable world for the past few years," he said.
"Events in Syria and the Middle East have clearly shown that chemical weapons are as relevant today as they were 100 years ago in the First World War."

Bunkall inside the gas chamber with the latest gear

It was in the laboratories at Porton Down that scientists developed a repellent to protect clothes against chemical weapons.
Their work over the last century has progressed gas mask technology considerably.
Early gas masks were horribly claustrophobic. Respirators were even developed for dogs and horses.
"The black veiled respirator was Britain's first response to the use of chlorine back in 1915," Colin explains, showing me a mess of fabric that was once the rushed response to German gas attacks on the Allied trenches in northern France.
"It's essentially cotton waste material soaked with various chemicals.
"You tie it around your mouth and hope for the best."

Entrance to one of the buildings at Porton Down

The modern version, in use since 2010, is called the second General Service Respirator.
It has a large wraparound visor for better vision and two oxygen canisters to help the wearer breathe more easily.
In a controlled gas chamber, filled with harmless smoke, I put it to the test.
It is first fitted to my face carefully.
If the seal leaks, harmful gases could seep in.
I also have to put on a military hazard suit.

One of the main buildings at the site - the only one we were allowed to film

I wear lightweight trousers and top but these are protected with the chemical repellent.
Finally I wear long black rubber gloves and pull the hood over my head.
On my back I have a heavy backpack - this contains the computer equipment that will feed live data back to analysts outside.
They will look for how many particles of gas are leaking into my mask.
In the chamber I'm put through some tests to put the mask under stress and replicate movement on the battlefield.
I have to run on the spot and jump on and off and platform.
It's hot, but my vision remains good - technology in the mask keeps it clear and stops the visor fogging up.
The mask works perfectly.
Porton Down is a military establishment, under the auspices of the Ministry of Defence, but they also work closely with the Home Office developing equipment for counter-terror police.
Although they prefer to work in secret, if terrorists do manage to get hold of chemical weapons, Porton Down's work will come into its own.