What is a primary use of the PHEL chart in heat management?

• A. It determines stay time and rotation out of heat stress areas according to exposure time
• B. It forecasts weather patterns
• C. It measures water salinity
• D. It schedules ship maintenance

Answer: (A)

The main idea tested is how heat exposure is managed through a tool that ties how long someone can safely stay in a hot area to the conditions they’re experiencing. The PHEL chart provides safe exposure durations and guides when to rotate personnel or pull them out for cooling based on how long they’ve been exposed and how hard they’re working. By using the chart, you plan stay times and rotations to keep core temperature and hydration within safe limits, reducing the risk of heat illness.

The other options don’t fit heat management purposes: weather forecasts come from meteorological tools, salinity is measured with separate marine instruments, and ship maintenance scheduling is based on maintenance plans, not heat-exposure data.