He has climbed several 8,000 metre peaks without using supplementary oxygen.

Many patients end up on supplementary oxygen and some will need a lung transplant.

This time, too, the ascent was made without supplementary oxygen.

It was in a solo climb without supplementary oxygen.

- and put about 40 per cent supplementary oxygen into the air.

He is the 6th person to accomplish that feat without the use of supplementary oxygen.

In May 1999 he spent a record 21 hours on the summit without supplementary oxygen, even sleeping there.

The ascent was performed by a new route and without the aid of supplementary oxygen.

He climbed alone without supplementary oxygen and skied down from 7,800 metres.

The ascent was made without the aid of supplementary oxygen.