The aim of the study is to investigate Work of Breathing of a person in simulated avalanche snow and consequent use of the measured data for judging which one of three simulated scenarios are alike while increasing hypercapnia in the simulated avalanche snow.

The study is a part of a university diploma thesis aimed at studying physiological conditions and development of breathing parameters of a person breathing in the simulated avalanche snow. The Investigator is measuring Work of Breathing in three scenarios: a) 2L air pocket, b) 2L air pocket with resistance compensation and c) no air pocket. The investigator hypothesize that the Work of Breathing during compensation of air pocket will be alike with no air pocket scenario, thus proving significance of the resistance reduction for survival. The aim of the study is to investigate the effect of Work of Breathing on gas exchange in subjects breathing into the simulated avalanche snow scenarios.

Inclusion Criteria:

• healthy and fit volunteers, classified as The American Society of Anesthesiologists class I
• without a smoking history

Exclusion Criteria:

• Tiffeneau Index less than 0.70
• any cardiovascular or respiratory condition