1.1 ,A traffic paint film freshly applied to a roadway, air strip, or parking lot may be exposed to rain of varying intensities shortly after application. This practice was designed to determine the relative water wash-off resistance of an applied traffic paint film under controlled laboratory conditions using a water faucet to simulate a heavy rain. This laboratory practice can also be used to compare conventional and fast-dry waterborne traffic paints and the effects of binders and other components in traffic for their relative ability to withstand a heavy rain soon after application.