Inch Of Mercury

An Inch of Mercury (symbol inHg) is a pressure unit that represents the force exerted by a one‑inch column of mercury under standard gravity at 0 °C, equivalent to about 3.386 kilopascals; it is commonly used to gauge atmospheric pressure, barometric readings, and vacuum levels in both practical and scientific settings. InHg is the traditional measurement for weather forecasting, aviation altimeters, and many industrial applications such as HVAC system calibration and tire‑pressure monitoring, where precise pressure data are critical for safety and performance. Because it directly relates to the height of a mercury column, the unit provides an intuitive, historically trusted way to translate pressure changes into readable values, making it indispensable for meteorologists, pilots, engineers, and researchers who need reliable, real‑time pressure information.