This article on the BBC grabbed my attention.
http://www.bbc.com/future/story/20180425-inside-the-cramped-confines-of-nasas-new-spacecraft?ocid=ww.social.link.email
According to this article, the habitability of the crew cabin in the Orion module or capsule will be not much more capacious per crew member than the Apollo command module was. However, these habitable volume,
or more accurately free volume
numbers are a little misleading. The Apollo Command Module had 10m3 of pressurized volume of which about 6.2m3 was free volume for about 2.07m3 per crew for a free volume to pressurized volume ratio of 62%. The Orion has about 19.35m3 of pressurized volume of which 9m3 is free volume for a free volume to pressuized volume ratio of 46%. The Orion's per crew pressurized volume is about 2.25m3. Astronaut Bowen appears to express some skepticism about whether the Orion constitutes progress over Apollo in habitability.
To give some perspective on how small these per crew volumes are, here is my paper Testing the Celentano Curve
in which I discuss pressurized volume per crew member on all the human spacecraft that have flown as of 2006. Will it soon be time to write an update?
Cohen, Marc M. (2009 April). Testing the Celentano Curve: An Empirical Survey of Predictions for Human Spacecraft Pressurized Volume (SAE 2008-01-2027). 38th International Conference on Environmental Systems (ICES), San Francisco, California, USA, 30 June - 2 July 2008. In, SAE International Journal of Aerospace (vol. 1, no. 1, p. 107-142). Warrendale, Pennsylvania, USA: Society of Automotive Engineers.
http://www.astrotecture.com/Human_System_Integration_files/SAE-2008-01-2027%20%282%29.pdf
