08 Tourmaster air bag suspension 120psi?

[univmd]

I have an 08 Tourmaster:

The sticker on the window says that I need to wait until the airbags are at least 120psi before driving off.

I only have two psi guages on my dash. Both have tire icons on them. Both go from 0-150psi, but only reach a max. of 113psi after starting up the engine (audio alarm goes off after 75psi).

I think one is for the front airbrakes and the other is for the rear airbrakes? Is it safe to drive off when the two guages above are only 113psi?

How do I measure airbag suspension psi to make sure they are at least 120psi? Do YOU measure air bag suspension psi?

With warm regards, James