well, ok, since you asked:

grabbing Sensym data book, SCX 15 A
full-scale span=90mV
15 psi=415 inches
1/415=0.0024
linearity and hysteresis is +/- 0.001

so it looks close, but doable if you're not too fussy.  i'm a
geologist, i'm not fussy, take heed.

alice
> John is looking to resolve pressure changes on the order of  0.25%
> Will hysteresis (sp??) be a problem?
> Jim
>
> Alice Campbell wrote:
>
> > Date sent:              Fri, 11 Feb 2000 08:51:40 -0800
> > use a 15 psin temperature-compensated absolute pressure sensor
> > and a 24-bit adc such as ltc2400 and throw away the 3 bytes you
> > dont need.  1 measurement per second max with this adc.  This is
> > for earth-- different psi for mars etc.
> > alice
> >
> > > Looking for ways to measure small changes in air pessure, in the range of
> > > 0" to 1" of water I guess. I don't know a lot about the different ways to
> > > measure air pressure.