The section in the On-line technical documentation titled "Valve Orifice Gas Conditions / Vent Pipe Exit Conditions/Subsonic Velocity Gas Conditions" references "Those points are shown in the figure on the opposite page".

What opposite page?

Also, the pressure value listed for the "Vent Pipe Exit Gas Conditions" - Is that pressure to be used in the API 520, 4.4.1 formula to determine the vertical thrust, F, or is the calculated "Thrust at the Vent Pipe Exit" to be used instead?