Personal Hygiene in Space

While astronauts comb their hair and shave with relative ease in space, other tasks such as using the bathroom present challenges unique to the microgravity environment. Regardless of the activity, astronauts and the people who design their equipment, try to make hygienic practices as familiar and practical as they are on Earth.

Clipping nails in space

CSA Astronaut Chris Hadfield shows us how the crew of the International Space Station clip their nails in space. (Credit: CSA/NASA)

Washing hands in space

CSA Astronaut Chris Hadfield demonstrates how astronauts wash their hands in the weightless environment of the International Space Station. (Credit: CSA/NASA)

How Do Astronauts Shower?

Cutting hair in space

CSA Astronaut Chris Hadfield gets a haircut in zero-g at the International Space Salon. (Credit: CSA/NASA)

In a microgravity environment, water clings to the body instead of running down it, so astronauts have sponge baths instead of regular showers. Unlike the space shuttle, there is a limited supply of water on the International Space Station (ISS) so taking sponge baths also conserves water. In space, astronauts use a no-rinse shampoo to wash their hair. They apply the shampoo using a towel, vigorously rub their hair and scalp and then use a towel to wipe their hair clean. Astronauts must not let loose hairs fall off the towel because floating hairs can create a safety hazard since they can be inhaled or aggravate an astronauts' eyes. Loose hair can also clog filters and affect air circulation and filtration.

Shaving in Space

Shaving in space is similar to shaving on Earth; astronauts just have to be careful not to let stray whiskers escape into the air. Astronauts shave with foam or an electric razor, but most prefer the latter, because it doesn't require water and automatically collects hair. While on short-duration flights astronauts don't require a haircut, on longer flights some astronauts need a trim. They cut their hair the same way as on Earth, but use a vacuum device so that stray hairs do not to float away.

Dental Care

Astronauts use the same toothpaste as on Earth and can even select their preferred brand. Instead of rinsing with water and then spitting into a sink, astronauts spit toothpaste into a towel. Recently, astronauts have been using edible toothpaste to reduce water waste. 

With long-duration flights, dental care is of increased concern. In 1973, Soviet Yuri Romanenko (father of current cosmonaut Roman Romanenko) developed a toothache on the 96-day Salyut 6 flight. The cosmonaut spent two weeks in pain before the crew returned to Earth. Since then, tools for dental care have been added to the crew's emergency medical kit. Moreover, astronauts will regularly visit the dentist's chair before their flight, anticipating any possible dental problems that could occur during their mission.

How Do Astronauts Use the Bathroom?

Bathroom from the Space Shuttle Columbia. Image courtesy of NASA.

A toilet with suctioning device aboard Space Shuttle Endeavour. July 31, 2009. (Credit: NASA)

Using the toilet is likely the most challenging aspect of personal hygiene in space. The washroom is very small with a raised bowl and seat for bowel movements. There is no gravity to keep the liquid in place, so to excrete solid waste astronauts use a water-free toilet. They position themselves over the toilet seat and secure themselves using body restraints. The astronaut turns on a series of fans that purify the air and a vacuum is used to imitate gravity for the waste. The air current moves solid waste from the toilet into a waste compartment. When they're finished they clean the toilet with wet wipes and dispose of the wipes and the toilet paper in a nearby container.

Both male and female astronauts have their own personal urination device that resembles a small cup. They connect the device to a long plastic tube that sticks out of the wall, and as they urinate an air current sucks the liquid along the tube and deposits it into a waste compartment. Astronauts can choose to secure themselves with straps while using the device. With all these extra steps, it takes about ten minutes longer to use the washroom in space than on Earth.