What is the standard pressure setting for flight levels, according to aviation regulations?

The standard pressure setting for flight levels, according to aviation regulations, is expressed in hectopascals (hPa), with a specific value of 1013.2 hPa. This standard is based on the International Standard Atmosphere (ISA), which provides a reference for pressure, temperature, and other atmospheric conditions at various altitudes.

Using hectopascals is beneficial in international aviation, as this unit aligns with the metric system, which is widely adopted around the globe. In practice, 1013.2 hPa is equivalent to 29.92 inches of mercury when converted, making this a universal reference for determining the appropriate altimeter settings during flight. As flight levels are defined in terms of pressure altitude, the standard atmospheric pressure provides essential uniformity and safety in air traffic management by ensuring that all aircraft are operating on the same pressure reference.

While inches of mercury and millibars are valid measurements for atmospheric pressure, they are used in different contexts or regional practices. The value of 30.00 inches of mercury is slightly higher than the standard pressure setting and could lead to discrepancies in altitude readings if consistently used over extended ranges. Meanwhile, 1000 millibars is approximately 100 hPa lower than the standard setting