Great question! Regional/zonal restrictions on the International Space Station… they do exist in my opinion, but we must be careful as to how we categorize them.
Having lived on board the ISS for five months in 2007, and then visiting for two weeks in 2010, I have first-hand experience as to how life is conducted “internationally” in low earth orbit. As the lone US astronaut during most of expedition 15 to the ISS, I had the privilege of living and working with two of the finest cosmonauts in history –Fyodor Yurchikin and Oleg Kotov. IMHO, I truly believe that they will become Russian space legends one day. They are already legends in my mind.
2007年，我在国际空间站上生活了五个月，然后在2010年访问了两个星期，因此我对低地球轨道上的人如何进行“国际间”交流有第一手“经验”。作为国际太空站（ISS） expedition 15任务中大部分时间里唯一的美国宇航员，我有幸与历史上最优秀的两名宇航员费奥多尔·尤尔奇金（Fyodor Yurchikin）和奥列格·科托夫（Oleg Kotov）一起生活和工作。恕我直言，我真的相信他们有一天会成为俄罗斯太空传奇。在我心中，它们已经是传奇。
As to zonal and/or regional restrictions in/on the ISS, there are none. It is more like a set of unwritten rules that astronauts and cosmonauts have to follow. In addition, since my retirement in 2013, it is possible that things have changed. Let me explain.
Inside the ISS in 2007, Russian cosmonauts and American astronauts had free reign. We could easily, and for no good reason, travel between the two segments. At that time, there were no JAXA (Japan) or ESA (European) modules… everything was either US or Russia, save the Canadian Robotic Manipulator/Arm.
Soyuz Sokol suit checkout after arrival to the ISS with STS-117.
It was understood however, that even though we had trained on each other’s ISS and the Russian’s Soyuz systems, we should refrain from doing anything independently in the segment/area that wasn’t “ours.” For example, if I was in the Russian segment, I would not do any work on anything without the watchful eyes of Fyodor or Oleg or clear direction from the Control Center in Moscow. This did not include going to the bathroom or preparing our food… we could all do that without worry of any restrictions (thank goodness!). But I will tell you, that if the urine tank was full, or the warning light in the toilet came on, I immediately hollered at my crew mates for confirmation of what I believed was going on and what we should do about it.
We had the same type of arrangement within the US segment. It was harder to police as Fyodor and Oleg had more US training than any cosmonauts in history. By virtue of their knowledge and abilities, it was hard to “slow them down,” when they were intent on making things right! Most times however, they knew exactly what to do, and together, we got it done correctly.
Outside the ISS was a bit different. There was one rule that US space walkers were always required to uphold. If a US astronaut was to translate over to the Russian segment, permission (verbal… over the communication loops) was required. More like a mental “thought jogger” than a true rule/danger avoidance, it forced us to acknowledge that we were heading into “new” territory where the rules were a bit different. For example, on the Russian segment, thrusters exist… with all the nastiness that comes with them. Avoidance of the areas where the plume and its by-products might contaminate a spacesuit was helpful as far as our multi-million dollar US taxpayer investment was concerned.
Astro Clay posing with the crew of ISS Expedition 23, April 2010.
2010年4月，美国宇航员Clay与ISS Expedition 23的机组人员合影。
As of 2010, the restrictions –if you can call them that– had begun to morph, and were more monetary in nature. As a member of the STS-131 crew, I returned to ISS at the time Oleg was serving as the station commander. Frank evening meal conversations w/my former crew mate uncovered new restrictions he was being forced to consider and institute. He was not, for example, allowed to perform any tasks in the US segment unless permission (read money received) had been given from his control center team in Moscow. It was not something that either of us felt was a good trend.
These days, I guess it’s the cost of doing business… in space.
Keep lookin’ up! Oh… and watch for new rules and regulations. After all, this is America!