Atmospheric pressure at sea level is

Atmospheric pressure at sea level is

• A. 14.7 psi
• B. 14.0 psi
• C. 15 psi
• D. 13.8 psi

Answer: (A)

Atmospheric pressure at sea level is defined by one atmosphere (1 atm), which is about 101.3 kilopascals. When you convert that to pounds per square inch, it comes out to roughly 14.7 psi. This value serves as the standard reference pressure in many firefighting calculations. Remember that gauges on equipment show pressure relative to atmosphere, so a reading of 0 psig corresponds to 14.7 psi of absolute pressure at sea level. The other numbers are rounded or approximate and do not match the established 1 atm value.

Atmospheric pressure at sea level is defined by one atmosphere (1 atm), which is about 101.3 kilopascals. When you convert that to pounds per square inch, it comes out to roughly 14.7 psi. This value serves as the standard reference pressure in many firefighting calculations. Remember that gauges on equipment show pressure relative to atmosphere, so a reading of 0 psig corresponds to 14.7 psi of absolute pressure at sea level. The other numbers are rounded or approximate and do not match the established 1 atm value.