Convert Inches of Mercury to Technical Atmospheres
Convert Inches of Mercury (inHg) to Technical Atmospheres (at) instantly and accurately.
Conversion Formula
at = inHg × 0.034531554
About Inches of Mercury
One inch of mercury (inHg) ≈ 3,386 Pa - the primary barometric pressure unit in US aviation and meteorology. ASOS weather stations, METARs, and altimeter settings in the US report in inHg. Standard sea-level pressure is 29.92 inHg. Altimeters are set to local QNH in inHg to maintain altitude reference. US barometers for home weather stations display inHg. Typical pressure range: 28.5-31.0 inHg in continental weather systems. Record low: ~25.70 inHg (Typhoon Tip, 1979). 1 inHg = 3,386.39 Pa.
About Technical Atmospheres
One technical atmosphere (at) = exactly 1 kgf/cm² = 98,066.5 Pa ≈ 0.968 standard atmospheres. The metric technical pressure unit used in pre-SI European and Japanese engineering for boilers, hydraulic cylinders, and compressed gas systems. A steam boiler at 10 at operates at 0.981 MPa; hydraulic presses are rated at 200-600 at. Still used parenthetically in old German and Japanese machinery manuals and standards (DIN 1301-3 legacy). Converts simply from kgf/cm²: 1 at ≡ 1 kgf/cm². 1 at = 98,066.5 Pa.
Quick Reference Table
| Inches of Mercury (inHg) | Technical Atmospheres (at) |
|---|---|
| 1 inHg | 0.0345316 at |
| 2 inHg | 0.0690631 at |
| 5 inHg | 0.172658 at |
| 10 inHg | 0.345316 at |
| 25 inHg | 0.863289 at |
| 50 inHg | 1.72658 at |
| 100 inHg | 3.45316 at |