## What is the Full Form of PSI?

The Full Form of PSI is Pound square per inch, which measures pressure commensurate to one pound-force per square inch. Pound square per inch is also known as pound-force per square inch. The PSI (Pounds square per inch) is a pressure unit mostly used in the United Kingdom and the United States of America. PSI is considered as the primary measure unit of pressure in the United States of America, which is used by almost all the pressure instruments and is being denoted in PSI pounds per square per inch. In Britain as well PSI is considered a widely used pressure unit, but the bar pressure unit has replaced the same. PSI, in simple words, is the measurement unit of pressure.

### Usage of PSI (Pounds Square Per Inch)

- As already mentioned in the above section that PSI is an imperial unit to measure pressure. PSI denotes it. For instance, one pound square per inch can be denoted as 1 PSI.
- Pounds Square per inch is used to measure the pressure in the area like industries as well as technical fields where it is required to measure gauge pressure.
- PSI is used to measure the pressure of gasses known as pneumatic pressure as well as liquid pressure known as hydraulic pressure.
- PSI is also used to measure the strength of tensile, which is also referred to as resistance to pull the forces, and the strength of elastic modulus referred to as resistance to deformation, which is utilized to sway over the material’s stiffness.
- PSI is being used to measure the strength of tensile of materials where 1000 PSI (KPSI).
- In a similar fashion, PSI is being used as the strength elastic modulus of materials where 10,00,000 (Millions) PSI (Mpsi).

### How to Calculate Pounds Per Square Inch?

The PSI can be calculated as follows. It can also be derived from Square inch units as defined below.

**Formula:**

PSI pound per square inch can be expressed with the following formula:

**1 PSI = 1 lbf/in 2**

Where,

**PSI**= Pound per Square Inch.**lbf**= Pound Force.**In 2**= Square Inches.- One pound per square inch is equal to pound-force being divided by the square inches.

### Examples of PSI

Following are the examples of PSI (Pounds per square inch):

- The water is being blown in tanks with high air pressure in terms of 4000 (Four thousand pounds per square inch.
- The extent of maximum permissible pressure in the tire of vehicles of 32 PSI (Pounds per square inch) is supposed to have an idle safe pressure, and it varies from 24 PSI to 32 PSI.
- The rate of increase in the pressure of sea has been observed by 17 pounds per square inch for every twenty feet.
- The pressure of 20 PSI (Pounds per square inch) on the differential resulted in the speed of the car.
- The PSI (Pounds square per inch) around us is expected to include the pressure of oxygen circa 3 PSI.

### Table for Conversion of PSI

**Source: **www.inchcalculator.com/

### Difference between Full Form of PSI and PSIA

The difference is derived from the different types of pressures; let’s look at the major differences between PSI and PSIA:

#### PSI

- Pounds square per inch, also known as pound-force per square inch, is a unit of pressure measurement is based on avoirdupois, and the same has been denoted by various abbreviations such as psi, lb/in, lb/in, lbf/sq in, lb/sq in, etc. PSI is the pressure which is the aftermath of the force of 1 pound-force being applied to an area of 1 square inch.
- 1 Pound per square inch is equal to 6894.757 Pa. From above, we can now easily convert the pound per square inch into standard atm (atmospheres). From the above calculation, we can observe the fact that one pound per square inch is equal to 14.7 pounds per square inch.

#### PSIA

- PSIA stands for Pound per square inch. Absolute explains the fact that stress or pressure is relative to the vacuum instead of the ambient pressure of the atmosphere. The atmospheric pressure at the level of the sea stands at circa 14.7 Psi, and this would be substantiated to any pressure being at sea level.
- PSIA is an absolute measure being measured relative to full vacuum, as mentioned in the above section. The vessel’s pressure, excluding any air molecules, will be equal to zero PSIA. The atmospheric pressure at the same time at sea level stands at 14.7 PSI.

### Conclusion – Full Form of PSI

PSI which stands for Pounds per square inch as described in the above sections that it is the basic unit of measurement of pressure being used in a number of pressure applications. PSI is normally implemented in cases of technical and industrial units for purposes like measuring the pressure of the tire, fuel storage and indicators including distributions, residual wastewater management, etc.

### Recommended Articles

This is a guide to the Full Form of PSI. Here we discuss the Definition and How to Calculate Pounds Per Square Inch along with the Difference between PSI and PSIA. You may also look at the following articles to learn more –