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How a Cold One Explains the Mystery of RH

Understanding Dew Point, Dry Bulb and Relative Humidity‍

RH or Relative Humidity is exactly that – It’s Relative!

RH is made up of two components – Dew Point and Dry Bulb. Once we understand these elements, and start controlling the amount of water in the air, we can master the drying and curing process.

This chart demonstrates the relationship between Dry Bulb Temperature and Dew point. Relative humidity changes based on movement in either of these elements. That means you can have a 62% RH with very different conditions.

DRY BULB – This is the actual temperature of the air the room.

DEW POINT – This is the temperature where water vapor starts to condense out of the air. When the dew point and the dry bulb are close together – the relative humidity will be high. When the dew point is well below the dry bulb the relative humidity is low. Dew point should always be below the dry bulb or…you will have rain in your room!

So why does water condense on our cold beer bottle? The dew point temperature of the air is above the temperature of the bottle of beer. In our next post we’ll talk about Vapor Pressure and how that relates to dew point and why managing Vapor Pressure is the key to great buds!

When we control the components of RH, we can eliminate swings in the environmental conditions that can damage our flowers, kill terpenes and potency.

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