A Maximum Absorbency Garment (MAG) is an adult-sized diaper with extra absorption material that NASA astronauts wear during liftoff, landing, and extra-vehicular activity (EVA) to absorb urine and feces.[1][2][3][4] It is worn by both male and female astronauts.[2] Astronauts can urinate into the MAG, and usually wait to defecate when they return to the spacecraft.[5] 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.[2] Nonetheless, the garment provides peace of mind for the astronauts.[2]
The MAG was developed because astronauts cannot remove their space suits during long operations, such as spacewalks that usually last for several hours.[6][7] Generally, three MAGs were given during space shuttle missions, one for launch, reentry, and an extra for spacewalking or for a second reentry attempt.[5][8] Astronauts drink about 2 L (2.1 US qt) of salty water before reentry since less fluid is retained in zero G.[9] Without the extra fluids, the astronauts might faint in Earth's gravity, further highlighting the potential necessity of the MAGs.[9] It is worn underneath the Liquid Cooling and Ventilation Garment (LCVG).[7]
During the Apollo era, astronauts used urine and fecal containment systems worn under spandex trunks.[10][5] The fecal containment device (FCD) was a bag attached directly to the body with an adhesive seal,[11] and the urine collection device (UCD) had a condom-like sheath attached to a tube and pouch.[8][10] Women joined the astronaut corps in 1978 and required devices with similar functions.[11] However, the early attempts to design feminized versions of the male devices were unsuccessful.[11] In the 1980s, NASA designed space diapers which were called Disposable Absorption Containment Trunks (DACTs).[5] These addressed the women's needs since it was comfortable, manageable, and resistant to leaks.[11] These diapers were first used in 1983, during the first Challenger mission.[5]
Disposable underwear, first introduced in the 1960s as baby's diapers then in 1980 for adult incontinence, appealed to NASA as a more practical option.[11] In 1988, the Maximum Absorbency Garment replaced the DACT for female astronauts.[12] NASA created the name Maximum Absorbency Garment to avoid using trade names.[11] Male astronauts then adopted the MAG as well.[11] In the 1990s, NASA ordered 3,200 of the diapers of the brand name Absorbencies, manufactured by a company that has folded.[8] In 2007, about a third of the supply remained.[8]
The MAGs are pulled up like shorts.[5] A powdery chemical absorbent called sodium polyacrylate is incorporated into the fabric of the garment.[5][8][13][9] Sodium polyacrylate can absorb around 300 times its weight in distilled water.[5][13] Assuming the astronaut urinates, the diaper would only need to be changed every eight to ten hours.[5] The MAG can hold a maximum of 2 L (2.1 US qt) of urine, blood, and/or feces.[1][14] The MAG absorbs the liquid and pulls it away from the skin.[5]
These garments gained attention in February 2007, when astronaut Lisa Nowak drove 1,450 km (901 mi) to attack Air Force officer Colleen Shipman out of jealousy for her former lover.[5][8][15] It was stated in a police report that Nowak said she used the diapers to avoid pit stops during her journey.[15] However, Nowak denied these claims and testified that she did not wear these diapers during her trip.[15]