Just to put my two cents in, with the fainting thing -- I think you will find stories about students fainting for most wind instruments. If one is unused to using so much air for extended lengths of time, it can and will cause you to faint.
It was something my instructor warned me about when I first started playing a wind instrument (a clarinet).

Thanks rumble!
Mike

if they are ready for the oboe than they shouldn't faint i have played for a while on mine with one breath and i have never fainted

At first, it may be hard to get a gentle/ low sound into the instrument, but it does become easier.

(There is actually a word for playing the oboe so loudly/ blowing so hard that your eyeballs pop out.)

This is not really a health risk, but a caution:

If your daughter does go to school with some playful and immature children, make sure that while she's playing or keeping the oboe in her mouth, that they "pop" or shove the oboe bell up into her mouth. The reed is sharp, and unlike flute, single reed or brass players, the reed will go straight into her mouth and pierce the upper part of her mouth, so be sure she is aware of that. I had a friend that knew another player that got blood all over her reed from that.

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Sorry, I meant that they DON'T pop the oboe up into her mouth. Sorry.

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I alos meant to say that when I play the Oboe, I have HORRIBLE headaches and I lose some of my hearing because of all the pressure. But I live with it...

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Yes, fainting and dizziness is also very popular with me...