No longer! The USAF, under the "CARE" program has reduced U2 equivalent cabin pressure from 30K feet to 15K feet.

Caution: Hypobaric Pressure- Regarding perhaps a more interesting study related to the Perlan 2 project. Our institute was asked to evaluate U-2 pilots following an increase in frequency of decompression sickness. The study found a significant number of white-matter lesions (e.g, stroke-like) in the brain of affected subjects. Some pilots (while in flight) were nearly incapacitated and others suffered long-term neurological changes. Why? The thinking is that these pilots operate at 70,000ft but cabin/suit pressure is maintained at only around 30,000ft!! I've heard mention that the Air Force is/has changing that to 15,000ft pressure alt (2013 cabin altitude reduction effort (CARE)). The Perlan 2 glider is pressurized to 14,000ft, according to their website info.


Public-distilled summary of findings:
http://www.reuters.com/article/us-he...97M0RT20130823
Original article:
https://www.ncbi.nlm.nih.gov/pmc/art...ihms488856.pdf
Mike