Waste disposal in space carries a load of unique problems. Any solution must be usable in gravity or weightless conditions, and must be workable within the size, weight and power constraints of spacecraft systems.
Despite much fiddling and adjustment throughout the early space program, NASA astronauts ultimately found the UCTA to be overly bulky, unsanitary and prone to problems, so NASA developed a Maximum Absorbency Garment, or MAG, for the shuttle program.
Although sometimes called space diapers, MAGs are more like hyperabsorbent bike shorts. Several thin layers of material move urine quickly away from the body, after which sodium polyacrylate, a super absorbent polymer (SAP) capable of taking on 400 times its weight in water, locks the moisture away. A MAG can soak up 2 liters (2.1 quarts) of liquid [source: O'Driscoll]. In a pinch, an astronaut can go 8 to 10 hours without needing a change [source: Gekas].
NASA didn't invent disposable diapers, adult diapers, sodium polyacrylate or SAPs. So it's not surprising that many adult diaper manufacturers attest that NASA did not influence their products. There is one somewhat ironic exception, however.
In 2007, astronaut Lisa Nowak thrust NASA "diapers" into the media spotlight when police in Orlando, Fla., charged her with the attempted kidnapping of U.S. Air Force Capt. Colleen Shipman. Early reports described Nowak driving 950 miles (1,529 kilometers) across five states while wearing an astronaut diaper so that she could skip restroom breaks [source: Fromm]. Court documents later revealed that police actually reported finding two used toddler-sized diapers in Nowak's vehicle, along with packs of diapers in her trunk. Nowak, a mother of three, denies wearing a diaper on the trip, saying the nappies were from 2005, when she, her family and the rest of Houston were evacuated before the advancing Hurricane Rita [source: Schneider].
There was one positive outcome of the Nowak story: According to Steve Goelman, CEO of Unique Wellness, it inspired his company to create adult diapers based on NASA designs. Goelman's company wanted a longwearing garment that, like the MAG, would quickly wick moisture away from the skin and lock it away, thereby avoiding skin irritation and other health problems.
"It is only through NASA's technology and idea that we can achieve this and apply it to the health care industry," said Goelman.
Goelman believes that Nowak's story may have also helped remove some of the stigma associated with adult incontinence, and that it raised awareness of other uses of adult diapers, such as by race car drivers and skiers.
It just goes to show, you never know where a good idea will come from.