Dew Point Calculator

Dew Point Calulator

When painting steel in cold or damp conditions you have to be wary of the dew point. This is when the steel sweats as soon as this happens or is likely to happen you cannot paint, no if's or but's just STOP.

Steels temperature needs to be 5 degrees c above the dew point to be ready to paint there is not a set temperature. You will need the following information at hand.

  • Temperature in your workshop or outside whereever you are painting
  • Humidity RH

Dew point

  • Now you know what the dew point is going to be on this particular day
  • Place a magnetic thermometre onto the steel to be painted
  • If the steels temperature is 5 c above the dew point it's ok to paint
  • If not warm the area untill both the steel and ambient temperature rises
  • Finally keep an eye on the themometer

Magnetic thermometres and hand held dew point calculators are available on our paint test equipment page CLICK HERE

If you would like to use a online dew point calcuator please CLICK HERE



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Rustbuster Ltd
Welland House
Cradge Bank
South Linconshire
PE11 3AN

01775 761 222

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