Is it ethical to hire sherpas when climbing Mount Everest?

The Everest climbing season that has just ended was marred by the worst accident in the mountain’s history. On 18 April 2014, 16 Nepalese sherpas died in an avalanche, and subsequent climbing expeditions were cancelled.1 2 The deaths of men from poor communities, hired to perform dangerous tasks for the sake of mountain climbing, provoked controversy.3

I used data on deaths above base camps from the Himalayan database,4 and definitions from a prior study.5 The aggregate risk of death for sherpas during a climbing season was 0.8% between 1922 and 2013. Including the recent disaster, 73% of all sherpas’ deaths resulted from objective hazards (avalanche, ice-fall collapse, crevasse fall, or falling rock or ice5) (figure⇓ and table⇓).

The question of whether it is acceptable to pay porters to assume risks for the benefit of others is an extreme variant of cases—common in medical ethics—where compensation and assumption of risk coincide. Consider debates about the sale …