"True vapor pressure" means the equilibrium partial pressure exerted by a VOL as determined in accordance with methods described in American Petroleum Institute (API) Chapter 19.2, "Evaporative Loss From Floating Roof Tanks", second edition, September 2003.

Source. (See Revision Note at chapter heading for Env-A 1200) #9933, eff 6-1-11; ss by #12899, eff 10-17-19