For people working at high altitude, such as construction workers, preventative measures are particularly important. As outlined above, it is essential to provide sufficient nutrients, rest, and insulation against the cold, as well as to limit labor intensity and duration of labor to avoid fatigue. Shift-work is also recommended and may entail 20-30 days of work at high altitude followed by a period of rest at low altitude to provide more effective resting conditions. Shift-work also reduces the incidence of chronic mountain sickness induced by long periods of physically demanding work at high altitude. It is also essential to ensure there is an adequate medical team to enable early detection, diagnosis, and treatment, should mountain sickness of HAPE occur.