he did mention iin relation to sport divin .
when divin with air the biggest factor we are concerned with are partial pressure of nitrogen and time . (depth and time)
if the ppn is reduced and when still divin on air tables "as i said above " there are greater safty margins .
oxtox is another issue that we have to consider . once mod's and times are observed no major problem .
o2 narcosis ?????????
for sport diving this is the gas of choice . for deeper depth which the op stated he was not interested in. different gases are a better choice .
so imho your reply was in need of a hug
