Chokes damages...Wanna know more

[Black Mamba]

During my grappling training some days ago I didn't hear my opponent tapping out (I don't think she did to be honest) and so I accidentally choked her out.
Since I heard that accidents like these can be very dangerous I'm very worried now to apply a choke while training. I think it was her fault cause she should have known when tap out but I feel worried anyway, which are the dangers if the hold is kept for too long? How many seconds are need for making the damages irreversible?
Thanks

 

[Bill Mattocks]

I am not a doctor, this is not medical advice:

http://en.wikipedia.org/wiki/Rear_naked_choke

Safe application

This choke, in either the figure-four or clasped-hand variation, is an extremely dangerous technique if used thoughtlessly or improperly. When applied as a blood choke in particular, the brain is immediately deprived of oxygen, leading (as mentioned above) to unconsciousness and ultimately (if not released) to brain damage or death. It is imperative, when using this technique, to be completely aware of your opponent's physical state, and to release the choke at any sign of your opponent losing consciousness or "tapping out." Rafiel Torre, a former mixed martial arts trainer and fighter, was convicted of killing a man using this technique, demonstrating that it is entirely lethal if misused.[4]

 

[Chris Parker]

Answered in your other thread, might be best to either delete or combine these two (Mods?). But Bill's information is absolutely correct. These techniques can quite literally be lethal.