Pounds Per Square Foot to Pascals (psf to Pa)
1 pound per square foot equals 47.88025898 pascals (rounded).
How to convert pounds per square foot to pascals
To convert pounds per square foot to pascals, multiply the number of pounds per square foot by 47.88025898. The factor is rounded to 10 significant digits. To go the other way, multiply pascals by 0.02088543423 (rounded).
pascals = pounds per square foot × 47.88025898
Example: 10 pounds per square foot = 478.8025898 pascals.
About these units
Pound Per Square Foot (psf)
About 47.88 pascals. Used in US structural engineering for distributed loads.
A square foot is 144 square inches, so one pound per square foot is one 144th of a psi, which comes to about 47.88 Pa; NIST gives 47.88026. The number is easy to picture: spread one pound-force evenly over a floor tile a foot across and that is the pressure, tiny compared with the 101,325 Pa of one standard atmosphere.
Building codes in the United States commonly state loads on floors and roofs this way, and snow and wind pressures are tabulated in the same unit. Metric countries use kilopascals or newtons per square metre instead, and 1 kPa is about 20.9 psf. Multiplying a psf figure by 144 gives psi, and by 47.88 gives pascals, so a 40 psf floor load is about 1.9 kPa.
1 pound per square foot = 47.88025898 pascals (approximately).
Sources: NIST SP 811, Appendix B.8; Wikipedia: Pounds per square inch
Pascal (Pa)
The SI unit of pressure: one newton per square meter. A very small unit; atmospheric pressure is about 101,325 Pa.
Blaise Pascal never saw a pascal, because the name was adopted by the 14th CGPM in 1971 for the newton per square meter. He did, however, earn the honor. In 1647 he published experiments on the vacuum, and on 19 September 1648 his brother-in-law Florin Périer carried a mercury barometer up the Puy de Dôme near Clermont, where the column stood at about 23 inches against about 26 at the base. Pascal had reasoned that air pressure should fall with altitude, and the result confirmed it.
One pascal is a tiny pressure, so the unit is mostly met with prefixes. Standard atmospheric pressure is 101,325 Pa, a typical sea-level reading is about 1,013 hPa, and the threshold of hearing in air is taken as a reference pressure of 20 micropascals. Building airtightness tests, in contrast, are run at 50 Pa.
Pascal is also remembered for hydrostatics, where he showed that pressure depends on height difference rather than the weight of the fluid, and for the hydraulic press.
The pascal is the reference unit for pressure on this site.
Sources: Wikipedia: Pascal (unit); Wikipedia: Blaise Pascal
Related conversions
- Pascals to pounds per square foot (reverse)
- Pounds per square foot to kilopascals
- Pounds per square foot to bars
- Pounds per square foot to standard atmospheres
- Pounds per square foot to PSI
- Kilopascals to pascals
- Bars to pascals
- Standard atmospheres to pascals
- PSI to pascals
- Hectopascals to pascals
- Megapascals to pascals
- Millibars to pascals
- Torr to pascals
- Millimeters of mercury to pascals
- Inches of mercury to pascals
- Gigapascals to pascals
- Kilopounds per square inch to pascals
See all pressure units.