Pressure cooker at 1 atmosphere?

AI Thread Summary
A standard pressure cooker operates at 15 psi, which is above atmospheric pressure, allowing water to boil at 120°C (250°F). Atmospheric pressure is approximately 1 bar, but the pressure inside the cooker is measured as gauge pressure, meaning it is the pressure above atmospheric levels. Therefore, the total pressure inside the cooker is about 2 bar (1 bar atmospheric plus 1 bar gauge pressure). This higher pressure raises the boiling point of water, enabling cooking at higher temperatures. Understanding gauge pressure is crucial to grasping how pressure cookers function effectively.
adoion
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Hi,

I just read that the operating pressure of a standard pressure cooker is 15 psi or about 1 bar and they claim that water boils at 120C or 250F at this pressure.

But atmospheric pressure is 1 bar in Paris and almost 1 bar in most countries in the world, here is a link I found http://www.engineeringtoolbox.com/boiling-point-water-d_926.html.

So please someone explain how a pressure cooker can boil its water at 120C with 1 bar of pressure and the atmosphere boils its at 100C with 1 bar of pressure. ?:) what's going on here guys?
 
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Google "gauge pressure."
 
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Likes Doug Huffman
All right so if it says 15 psi its actually 15 psi above atmosphere??
 
Correct.
 
Ok thanks man, very helpful :)
 

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