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The pascal (Pa) or kilopascal (kPa) as a unit of pressure measurement is widely used throughout the world and has largely replaced the pounds per square inch (psi) unit, except in some countries that still use the imperial measurement system or the US customary system, including the United States.
133 Pa 1 torr ≈ 1 mmHg [34] ±200 Pa ~140 dB: Threshold of pain pressure level for sound where prolonged exposure may lead to hearing loss [citation needed] ±300 Pa ±0.043 psi Lung air pressure difference moving the normal breaths of a person (only 0.3% of standard atmospheric pressure) [35] [36] 400–900 Pa 0.06–0.13 psi
Airwatt or air watt is a unit of measurement that represents the true suction power of vacuum cleaners. It is calculated by multiplying the airflow (in cubic metres per second) by the suction pressure (in pascals).
As the pascal is a very small unit relative to industrial pressures, the kilopascal is commonly used. 1000 kPa ≈ 145 lbf/in 2. Approximate conversions (rounded to some arbitrary number of digits, except when denoted by "≡") are shown in the following table.
The ground pressure of motorized vehicles is often compared with the ground pressure of a human foot, which can be 60 – 80 kPa while walking or as much as 13 MPa for a person in spike heels. [ 3 ] Increasing the size of the contact area on the ground (the footprint ) in relation to the weight decreases the unit ground pressure.
Acoustic impedance, denoted Z and measured in Pa·m −3 ·s in SI units, is defined by [2] = ^ ^ (), where ^ is the Laplace transform of sound pressure, [citation needed] ^ is the Laplace transform of sound volume flow rate.
An example of this is the air pressure in an automobile tire, which might be said to be "220 kPa (32 psi)", but is actually 220 kPa (32 psi) above atmospheric pressure. Since atmospheric pressure at sea level is about 100 kPa (14.7 psi), the absolute pressure in the tire is therefore about 320 kPa (46 psi).
In SI units, the unit is converted to the SI derived unit pascal (Pa), which is defined as one newton per square metre (N/m 2). A newton is equal to 1 kg⋅m/s 2, and a kilogram-force is 9.80665 N, [3] meaning that 1 kgf/cm 2 equals 98.0665 kilopascals (kPa).