ApplicationQuestion 53 of 100
Why is the dew point important when spray-painting exterior steel?
a.It determines paint color
b.It sets the required film thickness
c.Painting when the surface temperature is at or near the dew point can cause condensation, ruining adhesion
d.It only matters for interior work
Explanation
When a surface is at or below the dew point, moisture condenses on it, and painting over that invisible film causes blistering and adhesion failure, especially on metal. A common rule is to keep the surface at least about 5 F above the dew point. Painters monitor temperature, humidity, and dew point before coating.
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