Table of Contents

Materials Used to Build the EMU

Scientists needed to find a way for astronauts to deal with the extreme range of temperatures in space. Obviously, they couldn’t use very thick insulation on the suits—otherwise, the astronauts’ range of movement and sense of touch would be very limited. Instead, they combined a number of materials that protect the wearers and still allow them to do their job!

All of the materials chosen for the construction of the suit prevent the growth of bacteria and fungus. But the suits still need to get cleaned! The suits need special care after flight use. They were built to last for at least eight years.

We’ve made a list of some of the materials they used so you can get a feel about why they were chosen!

Layers and Layers of Materials

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A total of 14 layers make up the EMU.

Layers 1 to 3: The Liquid Cooling-and-Ventilation Garment (LCVG)

The first three inner layers make up the LCVG. The layer closest to the body is made up of a soft nylon tricot and the next two layers are made up of stretchy spandex and plastic tubes. These plastic tubes are used to transport cool water for temperature control.

Layer 4: The Pressure Garment

The next layer is the pressure bladder. It helps keep the body under a controlled amount of pressure while in space! The pressurized suit prevents the air in the astronaut’s lungs from rushing out and it also prevents the gases in the spacewalker’s body fluids from expanding and boiling off.

The pressure garment is made of nylon that’s dipped in rubber (urethane) at least six times to create an impermeable barrier between the pressure of pure oxygen inside the spacesuit and the vacuum of space outside of the suit.

Layer 5: The Pressure Garment Restraint

A layer of Dacron® restrains the pressure bladder. This material also helps to maintain the shape to the suit.

Layer 6: The Inner Lining of the Thermal Micrometeoroid Garment

This layer of Neoprene, coated with Nylon Ripstop, is the final layer of micrometeroid protection.

Layers 7 to 13: The Insulating Layers of the Thermal Micrometeoroid Garment

The next seven layers form the thermal micrometeoroid garment. These layers offer thermal protection.

Layer 14: Micrometeoroid/Tear Protection Layer

The outermost layer is an Ortho-Fabric which is a blend of Gortex®, Kevlar®, and Nomex®. The Ortho-Fabric is particularly good for thermal control and for protecting the pressure bladder and the pressure restraint layer from micrometeoroids.

Who’s Wearing Aluminum Foil?

EVA gloves are made of multi-layered pure aluminum foil which performs two jobs at the same time: it reflects or bounces heat back towards the body to keep the astronaut warm and it also deflects heat from the Sun so that the body doesn't get too hot.

This material is so effective that it is used for spacecraft and satellites, too!

Sunglasses Made for Space!

Astronauts are exposed to the harmful effects of the Sun including radiation and ultraviolet (UV) rays. Research has taught us that large doses of UV light can cause cancer, so radiation-blocking lenses, to be used in the visor of the space helmet, were created to protect the EVA astronaut.

These lenses block 99% of the UV rays so the astronaut’s eyes are protected during their spacewalk.