At what depth does a diver experience a correction factor of +4?

The correction factor of +4 is indicative of a specific adjustment applied to a diver’s calculations based on the depth at which they are operating. In diving, as one descends deeper into the water, the pressure increases, which affects various physiological and physical characteristics related to the diver's behavior and their equipment.

When a diver reaches depths between 201 and 300 feet, they experience significant increases in pressure, which necessitates the application of a greater correction factor. This is due to the physiological stresses and complications that arise at these depths, including the need for decompression considerations and adjustments in buoyancy. The standard practice in underwater rescue and diving operations is to apply these correction factors based on established depth ranges to ensure safety and accuracy.

Depths above 200 feet typically involve more complex conditions such as increased nitrogen narcosis risk and may require special breathing mixtures. Therefore, the correction factor of +4 is specifically designed for divers operating within the 201-300 feet range, making this the correct response to the question.