Steam Properties

The saturation line comes from IAPWS-IF97, so pressure and temperature are exact to the international standard rather than read off a chart. Properties are interpolated from the saturated table. The number most people are actually after is h_fg — the latent heat, about 2257 kJ/kg at atmospheric pressure, and roughly five times the energy needed to heat the same water from freezing to boiling.

Pressures are ABSOLUTE, not gauge — add 1.013 bar to a gauge reading. Enthalpy is referenced to 0 kJ/kg for saturated liquid at the triple point, the usual convention. Superheated steam is not covered: this is the saturation line only, so a boiler with a superheater needs a full steam table or IF97 Region 2. Flash steam is computed for condensate at the stated pressure let down to the flash pressure.