Danger of Oxygen During Labor ?

I am wanting to set up my bedroom like a hospital room, with all the necessary supplies. I am planning on going next week to the local hospital to find out where I can get an oxygen tank and oxygen. Even if I were to get an oxygen tank shipped from America to Tanzania, I might not be able to have a way to get it filled. Researching oxygen got me wondering when/if I should use it and are there any dangers/risk from over using it. From what I have seen is that if there is an obvious change in the babies heart rate, then you should give the mom some oxygen, and get her changing positions. But in America the practice of giving oxygen, just in case, is becoming more and more common. Some say that oxygen is just air and that it causes no danger, so why not? I am doing more research on this but this is one article stating their trial results on this topic. It states,

"The effect of maternal oxygen administration during the second stage of labor on umbilical cord blood gas values: a randomized controlled prospective trial

Article Abstract:

Administering oxygen for longer than 10 minutes during pushing appears to have an adverse effect on the fetus. Eighty-six women in normal labor with a healthy, term fetus were randomly assigned to receive oxygen via mask during the pushing phase of labor. A blood sample was taken from the umbilical vein after birth and analyzed. As the length of oxygen therapy increased beyond 10 minutes, the pH of the baby's blood declined. Low pH is a symptom of decreased oxygen, although no baby experienced fetal distress. Results may not be applicable to different situations, as, for example, when the baby already lacks oxygen. Several studies have shown that although oxygen is often administered liberally in labor to the mother to improve fetal oxygenation, its use can have this adverse effect. Laboratory studies have shown that umbilical and placental blood vessels constrict in the presence of abnormally high amounts of oxygen, which may be the cause of this phenomenon."

Read more: http://www.faqs.org/abstracts/Health/The-effect-of-maternal-oxygen-administration-during-the-second-stage-of-labor-on-umbilical-cord-bloo.html#ixzz1JfcGDBeg