Chevrolet 1999 Tahoe Owner's Manual page 286

CAUTION:
Gasoline vapor is highly flammable. It burns
violently, and that can cause very bad injuries.
Don't smoke if you're near gasoline or refueling
your vehicle. Keep sparks, flames and smoking
materials away from gasoline.
6-6
While refueling, let the cap hang by the tether below the
fuel filler neck.
To remove the cap, turn it slowly to the left
(counterclockwise).
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