Convert Technical Atmospheres to Millimeters of Mercury

Convert Technical Atmospheres (at) to Millimeters of Mercury (mmHg) instantly and accurately.

Technical Atmospheres (at)
Millimeters of Mercury (mmHg)

Conversion Formula

mmHg = at × 735.5591353

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.

About Millimeters of Mercury

One millimetre of mercury (mmHg) = pressure from 1 mm of mercury at 0°C and standard gravity = 133.322 Pa. Clinical medicine worldwide uses mmHg for blood pressure (normal ~120/80 mmHg) and for gas partial pressures in physiology: arterial O₂ ~95-100 mmHg; CO₂ ~40 mmHg; alveolar O₂ ~104 mmHg. Ophthalmologists measure intraocular pressure in mmHg (normal 10-21; glaucoma risk above 21). Vacuum equipment ratings are also given in mmHg. 760 mmHg = 1 atm. 1 mmHg = 133.322 Pa.

Quick Reference Table

Technical Atmospheres (at)Millimeters of Mercury (mmHg)
1 at735.559 mmHg
2 at1471.12 mmHg
5 at3677.8 mmHg
10 at7355.59 mmHg
25 at18389 mmHg
50 at36778 mmHg
100 at73555.9 mmHg

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