What are the reference conditions for measuring volume flow rate?

There are two different reference conditions.

One is N.T.P. and other is called S.T.P.

Normal condition of Temperature and Pressure is NTP.
Standard condition of Temperature and Pressure is STP.

The definitions for these conditions are defined but are interchanging in various countries. In India they are defined as follows,

NTP: 0° C Temperature and 1 Atmosphere Pressure.
STP: 15° C Temperature and 1 Atmosphere Pressure.

1 Like