SOME COMMON UNITS of PRESSURE
1 Pa Pascal = 1 N/m2 (The SI unit)
1 psi = 1 lb/in2 (English unit) = 6,891 Pa
1 Bar = 105 N/m2 = 100 kPa ≈ 1 atm
1 Tor = 1 mm Hg = 133.3 Pa ≈ 1 kPa
1 atm = 101.3 kPa = 760 mm Hg = 29.92 in Hg = 14.70 psi

TYPICAL VALUES OF PRESSURE
Pressures Values (Pa = N/m2)
Best laboratory vacuum ≈ 10-12 Pa
Sunlight at the Earth's surface ≈ 3 mPa
Rock Concert (Pressure on the ear drum)* ≈ 10 Pa
Lincoln Penny lying flat (balanced on edge)* 85 Pa (≈ 16 kPa)
Blood pressure* 1 kPa - 15 kPa
Recyclable Coffee Mug, 3/4 full with a raised edge on the bottom
(flat bottom)*
≈ 10 kPa
(1 kPa)
Surface of Mars Air Pressure ≈ 1 kPa
Atmospheric Pressure of the Earth:
10 km altitude
100 km altitude

≈ 26 kPa
@ 0.1 Pa
Normal Atmospheric Air Pressure 1 atm = 101.3 kPa = 14.5 psi
Tires of a typical car against the ground (This is also approximately
same as the pressure inside the tire)*

≈ 32 psi = 220 kPa
Household water pressure* ≈ 250 kPa
Hydraulic Elevator Pump* ≈ 300 kPa
Under the foot of an Elephant* ≈ 1 MPa
Ballet dancer on one foot* ≈ 2 MPa
Phonograph stylus tip* ≈ 10 MPa
Deep Trenches in Pacific Ocean ≈ 100 MPa
Center of the Earth ≈ 4x1011Pa = 4x106atm
Center of the Sun ≈ 1015 Pa = 109 atm
* Many of the values above are gauge pressures