"Shirt-sleeve environment" is a term used in

aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engine ...

design to describe the interior of an aircraft in which no special clothing need be worn. Early aircraft had no internal pressurization, so the crews of those that reached the stratosphere had to be

garb Garb may refer to: * Clothing * Garb, a wheat sheaf (agriculture) A sheaf (/ʃiːf/) is a bunch of cereal-crop stems bound together after reaping, traditionally by sickle, later by scythe or, after its introduction in 1872, by a mechanical r ...

ed to withstand the low temperature and pressure of the air outside. Respirator masks needed to cover the mouth and nose. Silk socks were worn to retain heat. Sometimes leather

clothing Clothing (also known as clothes, apparel, and attire) are items worn on the body. Typically, clothing is made of fabrics or textiles, but over time it has included garments made from animal skin and other thin sheets of materials and natural ...

, such as boots, were electrically heated. When jet fighter aircraft reached still higher altitudes, something similar to a

space suit A space suit or spacesuit is a garment worn to keep a human alive in the harsh environment of outer space, vacuum and temperature extremes. Space suits are often worn inside spacecraft as a safety precaution in case of loss of cabin pressure, ...

had to be worn, and pilots of the highest reconnaissance aircraft wore real space suits. Commercial

jet airliner A jet airliner or jetliner is an airliner powered by jet engines (passenger jet aircraft). Airliners usually have two or four jet engines; three-engined designs were popular in the 1970s but are less common today. Airliners are commonly clas ...

s fly in the stratosphere, but because they are pressurized, they could be said to have a shirt-sleeve environment. Crews of the US

Apollo spacecraft The Apollo spacecraft was composed of three parts designed to accomplish the American Apollo program's goal of landing astronauts on the Moon by the end of the 1960s and returning them safely to Earth. The expendable (single-use) spacecraft ...

always began the flight phases of launch, docking, and

re-entry Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. There are two main types of atmospheric entry: ''uncontrolled entry'', such as the entr ...

in space suits, although they could remove them for many hours. The Soviets tried to perfect this to save weight. This worked well, until an accidental depressurization on entry resulted in the deaths of an entire Soyuz crew. Protocols were changed shortly thereafter to require at least partial spacesuits. Early Soyuz spacecraft had no provision for space suits in the re-entry module, although the

orbital module The orbital module is a compartment of some space capsules used only in orbit. It is separated from the crewed reentry capsule before reentry. The orbital module provides 'habitat' space to use in orbit, while the reentry capsule tends to be focu ...

was intended for use as an

airlock An airlock, air-lock or air lock, often abbreviated to just lock, is a compartment with doors which can be sealed against pressure which permits the passage of people and objects between environments of differing pressure or atmospheric compo ...

. Thus these operated in a shirt-sleeve environment except for spacewalks. This term is also used in

science fiction Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, parallel uni ...

to describe an alien

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

with an atmosphere breathable by humans without special equipment. The

Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program ...

Spacelab Spacelab was a reusable laboratory developed by European Space Agency (ESA) and used on certain spaceflights flown by the Space Shuttle. The laboratory comprised multiple components, including a pressurized module, an unpressurized carrier, ...

Habitable module was an area with expanded volume for astronauts to work in a shirt sleeve environment and had space for equipment racks and related support equipment for operations in

Low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...

. One of the goals for MOLAB rover was to achieve a shirt-sleeve environment (compared to a

lunar rover A lunar rover or Moon rover is a space exploration vehicle designed to move across the surface of the Moon. The Apollo Program's Lunar Roving Vehicle was driven on the Moon by members of three American crews, Apollo 15, 16, and 17. Other rov ...

which was open to space and required the use of space suits to operate).{{Cite book, url=https://books.google.com/books?id=MoKoBQAAQBAJ&q=Shirt-sleeve+environment&pg=PA370, title=Advances in Space Science and Technology, last=Ordway, first=Frederick I., date=2014-12-02, publisher=Academic Press, isbn=9781483224701, language=en One of the considerations was the habitable volume that could be occupied.

References

Aerospace engineering