gas-mask

In January 1958, two medical officers at Porton Down, Britain’s military science facility, exposed their forearms to 50-microgram droplets of a substance called VX, which was a new, fast-acting nerve agent that could kill by seeping through the skin.

http://blogs.discovermagazine.com/crux/2017/02/24/vx-nerve-agent-the-deadly-weapon-engineered-in-secret/#.WLEBvfkrKM9