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To convert from pound per square inch (psi) to meter of water @ 4°C (mH2O), use the following formula:
With is the ratio between the base units kilopascal (kPa) and kilopound per square inch (ksi).
Let's convert 5 pound per square inch (psi) to meter of water @ 4°C (mH2O).
Using the formula:
Therefore, 5 pound per square inch (psi) is equal to meter of water @ 4°C (mH2O).
Here are some quick reference conversions from pound per square inch (psi) to meter of water @ 4°C (mH2O):
| pounds per square inch | meters of water @ 4°C |
|---|---|
| 0.000001 psi | mH2O |
| 0.001 psi | mH2O |
| 0.1 psi | mH2O |
| 1 psi | mH2O |
| 2 psi | mH2O |
| 3 psi | mH2O |
| 4 psi | mH2O |
| 5 psi | mH2O |
| 6 psi | mH2O |
| 7 psi | mH2O |
| 8 psi | mH2O |
| 9 psi | mH2O |
| 10 psi | mH2O |
| 20 psi | mH2O |
| 30 psi | mH2O |
| 40 psi | mH2O |
| 50 psi | mH2O |
| 100 psi | mH2O |
| 1000 psi | mH2O |
| 10000 psi | mH2O |
For all Pressure converters, choose units using the From/To dropdowns above.
A pound per square inch (PSI) is a unit of pressure commonly used in the imperial system (which is standard in the United States).
It measures the amount of force applied over a single square inch of area.
PSI is a critical measurement for safety and performance in many common items, including:
Vehicle Tires: Proper tire pressure (PSI) ensures optimal handling, fuel efficiency, and tire life. You can find the recommended level on a sticker inside the driver's door.
Home Water Pressure: Affects everything from shower performance to how well appliances like dishwashers and washing machines function.
Sports Equipment: Items like footballs, basketballs, and soccer balls require a specific PSI to perform correctly and safely.
Tools: Air compressors, pressure washers, and paint sprayers all have specific PSI ratings for safe and effective operation.
While PSI is standard in the imperial system, scientific and international contexts use metric (SI) units like the Pascal (Pa) and the bar.
PSI to Pascal (Pa): The official SI unit for pressure.
1 PSI ≈ 6,894.76 Pascals (or 6.895 kilopascals, kPa).
PSI to Bar: A common unit in automotive and weather contexts. 1 bar is roughly equal to atmospheric pressure at sea level.
1 PSI ≈ 0.0689 bar.
The term "PSI" can be specified further to give more context:
PSIG (Pound-force per square inch gauge): Measures pressure relative to the surrounding atmospheric pressure. This is the most common measurement, used by a standard tire gauge.
PSIA (Pound-force per square inch absolute): Measures pressure relative to a perfect vacuum (absolute zero pressure).
The formula is: PSIA = PSIG + local atmospheric pressure.
PSID (Pound-force per square inch differential): Measures the difference in pressure between two separate points in a system, such as across a filter or valve.
A meter of water @ 4°C (mH2O) is a metric unit used to measure pressure.
It is precisely defined as 9.80665 kilopascals (kPa).
The specific temperature of 4°C (39.2°F) is key because this is the point where pure water is at its heaviest or most dense (approximately 999.972 kg/m3).
Using this temperature provides a stable and reliable standard for defining pressure.
This precision is essential in scientific and engineering fields like hydraulics and fluid mechanics, ensuring that measurements of pressure head are consistent and accurate across different applications and locations.
The unit "meter of water" (mH2O) is frequently used in civil engineering, hydrology, and irrigation to measure water levels and pressure.
It provides an intuitive way to express the pressure exerted by a column of water, such as the water level in a reservoir, dam, or groundwater well. This measurement is sometimes referred to as the 'piezometric head'.
It is also commonly used to specify the performance of pumps, indicating the height to which a pump can lift water.
For practical use, it's often helpful to know how mH2O converts to other common pressure units.
One mH2O is equal to:
These conversion factors allow engineers and scientists to easily translate pressure specifications between different international and imperial systems.