Maximum Absorbency Garment

A Maximum Absorbency Garment (MAG) is a piece of clothing NASA astronauts wear during liftoff, landing, and extra-vehicular activity (EVA) to absorb urine and feces. It is worn by both male and female astronauts. Astronauts can urinate into the MAG, and usually wait to defecate when they return to the spacecraft. However, the MAG is rarely used for this purpose, since the astronauts use the facilities of the station before EVA and also time the consumption of the in-suit water. Nonetheless, the garment provides peace of mind for the astronauts.

The adult-sized diaper with extra absorption material is used because astronauts cannot remove their space suits during long operations, such as spacewalks that usually last for several hours. Generally, three MAGs were given during space shuttle missions, one for launch, reentry, and an extra for spacewalking or for a second reentry attempt. Astronauts drink about 2 L (2.1 US qt) of salty water before reentry since fewer fluids are retained in zero G. Without the extra fluids, the astronauts might faint in Earth's gravity, further highlighting the potential necessity of the MAGs. It is worn underneath the Liquid Cooling and Ventilation Garment (LCVG).

During the Apollo era, astronauts used urine and fecal containment systems worn under spandex trunks. The fecal containment device (FCD) was a bag attached directly to the body with an adhesive seal, and the urine collection device (UCD) had a condom-like sheath attached to a tube and pouch. Women joined the astronaut corps in 1978 and required devices with similar functions. However, the early attempts to design feminized versions of the male devices were unsuccessful. In the 1980s, NASA designed space diapers which were called Disposable Absorption Containment Trunks (DACTs). These addressed the women's needs since it was comfortable, manageable, and resistant to leaks. These diapers were first used in 1983, during the first Challenger mission.

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