It is expected that the oxygen
percentage in your body could be lowered from 20% to
15% during this experiment. You will have complete control
of how long you hold your breath and can breath when
you feel discomfort and want to breath. You may feel
a tickling sensation in your throat because the gas
is dry. In addition your voice will change briefly after
breathing the Helium. This is no concern and your voice
will change quickly back to normal after you stop breathing
the Helium gas. No other effects from the Helium are
expected.
