Don’t worry about it too much, just do not use it near a candle or other open flame. It doesn’t spontaneously combust. The flammability range is between 2 and 12.7% of vapor in air. While in the bottle, stored away from heat and naked flame it is quite safe. The odorless thinners are also flammable, as is acetone, all need to be stored in cool place, in securely closed containers, away from open flame and heat.