Technical Atmosphere is similar although not the same value as the standard atmosphere pressure unit (atm) and both have been used historically to relate a pressure value to multiples of atmospheric pressure. 1 Technical Atmosphere is defined as being exactly equal to 98,066.5 pascals.

The at pressure unit can be occasionally found on water resistant watches to indicate the maximum depth rating, particularly on European brands. However the unit has been largely phased out and the average atmospheric pressure is now mostly defined as 1 atm (101325 Pa) for weather and aviation or more coomonly 1 bar (100,000 Pa) for industrial and general purposes.

Technical Atmosphere is some times written as ‘ata’ which is the short way of writing ‘at absolute’.

Equivalent values for 1 at in other pressure units can be found in the list below.

To convert any pressure unit into Technical Atmospheres click on the relevant unit below.

Use the pressure converter page to convert many different values to and from technical atmosphere units.

**Atmospheric pressure measurement products**

- Barometric range 800-1100mb IECEx approved intrinsically safe pressure transmitter
- Wind power barometric pressure visual monitor with alarm relay switches
- 10 metre range non-vented submersible absolute range pressure and barometric sensor
- Atmospheric Pressure Data Loggers

## Conversion Factors

- 0.980665 bar
- 14.2233 psi
- 980.665 mbar
- 98066.5 N/m²
- 98066.5 Pa
- 980.665 hPa
- 98.0665 kPa
- 0.0980665 MPa
- 1 kg/cm²
- 10000 mmH2O 4°C (39.2°F)
- 1000 cmH2O 4°C (39.2°F)
- 10 mH2O 4°C (39.2°F)
- 393.701 inH2O 4°C (39.2°F)
- 32.8084 ftH2O 4°C (39.2°F)
- 735.559 mmHg 0°C (32°F)
- 73.5559 cmHg 0°C (32°F)
- 28.9590 inHg 0°C (32°F)
- 735.559 Torr
- 735559 mTorr
- 0.96784 atm
- 1 at
- 980665 dyn/cm²
- 227.573 oz/in²
- 735559 µHg 0°C (32°F)
- 0.00634971 tsi (uk, long)
- 0.00711167 tsi (usa, short)
- 1.02408 tsf (usa, short)
- 2048.16 psf
- 1000 g/cm²

*Please note that the conversion factors above are accurate to 6 significant figures.*

**Atmospheric pressure measurement products**

- 500-1100 mbar absolute 0-10Vdc out air pressure sensor for meteorological use
- Air flow normalising calculation barometric pressure transmitter
- Gas analyser 75-125 kPa absolute range 0.5-4.5V ratiometric output pressure sensor
- SIL 2 certified 800 to 1200 mbar abs range air pressure transmitter

## Help

### ata meaning

*What is meaning of “ata” and how does it convert into kgf/sq.cm?*

ata means a pressure reading in technical atmosphere units (at) which are referenced to a perfect vacuum (absolute).

### at conversion to kg/cm2

Both units equal the same: 1 ata = 1 technical atmosphere absolute = 1 kgf/cm² absolute

1 ata should not be confused with 1 atm which is a slightly different value.

### 325 at to psi

*What is the conversion from 325 at into psi?*

The conversion is 325 at = 4622.58657 psi

**Atmospheric pressure measurement products**

- Barometric range 800-1100mb IECEx approved intrinsically safe pressure transmitter
- TSA Precision Pressure Transmitter
- Marine approved atmospheric pressure sensor
- Outside HVAC 900-1100 mbar abs baro range 4-20mA signal pressure sensor

## Measurement Unit Related Terms

More pages related to measurement unit technical terms.

- atm – Standard Atmosphere Pressure Unit
- bar Pressure Unit
- cmH2O – Centimetres of Water Column at 4 deg C Pressure Unit
- cmHg – Centimetres of Mercury at 0 deg C Pressure Unit
- daPa – Dekapascal Pressure Unit
- dyn/cm² – Dyne per Square Centimetre Pressure Unit
- ftH2O – Feet of Water Column at 4 deg C Pressure Unit
- g – Acceleration due to Gravity
- g/cm² – Grams per Square Centimetre Pressure Unit
- hPa – Hectopascal Pressure Unit
- inH2O – Inches of Water Column at 4 deg C Pressure Unit
- inHg – Inches of Mercury at 0 degrees C Pressure Unit
- kg/cm² – Kilogram per Square Centimetre Pressure Unit
- kg/mm² – Kilogram per Square Millimetre Pressure Unit
- kPa – Kilopascal Pressure Unit
- ksi – Kilopounds per Square Inch Pressure Unit
- mbar – Millibar Pressure Unit
- mH2O – Metres of Water Gauge at 4 deg C Pressure Unit
- mmH2O – Millimetres of Water Column at 4 deg C Pressure Unit
- mmHg – Millimetres of Mercury at 0 deg C Pressure Unit
- MPa – Megapascal Pressure Unit
- mPa – Millipascal Pressure Unit
- mTorr – Millitorr Pressure Unit
- N/cm² – Newton per Square Centimetre Pressure Unit
- N/m2 – Newton per Square Metre Pressure Unit
- N/mm² – Newton per Square Millimetre Pressure Unit
- oz/in² – Ounce per Square Inch Pressure Unit
- Pa – Pascal Pressure Unit
- Pressure
- Pressure Units
- psf – Pounds per Square Foot Pressure Unit
- psi – Pounds per Square Inch Pressure Unit
- Specific Gravity
- Torr Pressure Unit
- tsf – Tons per Square Foot (USA, Short) Pressure Unit
- tsi – Tons per Square Inch (UK, Long) Pressure Unit
- tsi – Tons per Square Inch (USA, Short) Pressure Unit
- Water Density
- µHg – Micron of Mercury at 0 deg C Pressure Unit