Which statement best describes hourly sweat loss in hot and humid environments?

• A. 2 quarts per hour
• B. 0.5 liters per hour
• C. 3-4 liters per hour
• D. 1-2 liters per hour

Answer: (D)

In hot, humid conditions with turnout gear, sweat loss during heavy work is substantial but typically falls in a range around 1–2 liters per hour. The gear impedes evaporation, so the body sweats a lot to try to cool, but the rate varies among individuals and situations. Values as low as 0.5 L/hour don’t reflect the effort and gear, while 3–4 L/hour would be extreme and unsustainable for most people. Saying 2 quarts per hour is close to the 1.9 L/hour mark, but the explicit 1–2 liters per hour range best captures the common, practical amount across conditions. This is why 1–2 L/hour is the best description.