The DuPont Tychem 10000 hazmat suit is overkill for just about every situation. That’s the point. The getup blocks more than 320 nasty chemicals for at least 30 minutes. Some, such as the VX nerve agent (a deadly weapon), won’t breach it for eight hours or more, which is why first responders don the garments when wading into clouds of noxious death. Here’s how it keeps its occupants from melting.
The suit is a sandwich of materials. The middle layer is roughly 1/8-inch-thick puncture-resistant polypropylene, and a coating on both sides includes dozens of plastic polymers. Each of those has its own protective responsibility, like stopping sarin gas.
The face shield gives rescuers a 220-degree field of view, and it leaves enough room for a scuba-style respirator to fit underneath it—necessary since the garb is airtight. The window is a combination of heat-tolerant Teflon and durable PVC plastic.
Double-layered gloves allow for both dexterity and protection. The outer skin is flexible neoprene, which lets workers grip tools better than the slippery suit material would. The interior lining is the same toxin-blocking coating that encases the rest of the outfit.
The stitching—normally the weakest part of clothing—is this walking bunker’s strongest point. Double-sewn lines of polyester thread connect panels, and DuPont finishes each junction with a strip of chemical-blocking tape on the inside and outside.
This article was originally published in the Winter 2018 Danger issue of Popular Science.