Abstract. The volume magnetic susceptibility of moist air χ_m(ma) is needed to correct the results of certain experiments to vacuum conditions. This paper derives an appropriate equation for χ_m(ma) for which pressure, temperature, relative humidity, and carbon dioxide content are variable parameters. The derived equation also depends sensitively on the molar susceptibility of oxygen, for which the handbook values are inconsistent by about 1.4%. The equation resolves this discrepancy in part.

Print publication: Issue 1 (February 1998)