Re: PSID at MSL

Re: PSID at MSL   (02/06/2013, 5:04 PM)

Assuming MSL is mean sea level pressure, then at sea level, 1 atmosphere of pressure = 14.696 psi.

If you are converting absolute pressure, then 40 psig = 54.696 psia using the lower conversion form on this page:

https://www.convertunits.com/from/psig/to/psia

Basically, you add one extra atmosphere to the psig reading to get the absolute gauge pressure.

If you are actually looking for PSID though, then the "d" means you want differential pressure. In this case, the differential pressure is still 40 psid. The confusion with differential pressure is determining a reference point, so if it's relative to sea level, then you would get 54.696 psid.