Good indoor environment quality (IEQ) can improve the health, comfort and productivity of your building's occupants. But what happens when your building struggles with humidity issues? Such issues can not only make occupants less comfortable, but they can decrease productivity, create an unsafe environment, enable the growth of harmful contaminants, generate static electricity and cause structural damage to the building.

About humidity

When we talk about humidity, we are talking about relative humidity. This compares the amount of water vapor in the air with how much it can hold at a certain temperature. The dew point is when the air is 100% saturated.

The ASHRAE 55 standard recommends target temperature and humidity zones based on seasons. In summer, the target should be a temperature range of 72°F to 82°F with relative humidity levels between 25% and 60%. During the winter, the target shifts. Temperatures between 70°F and 75°F and relative humidity between 30% and 60% should be the goal.

Humidity control methods

So, how can we control humidity to stay within those zones? One way to control humidity is through air conditioning cooling coils. The air is cooled down beyond the dew point and past the desired temperature, creating condensation and reducing the amount of moisture in the air. Then the air is warmed slightly to the desired temperature without adding any moisture back into the air. This increases the temperature with the same amount of moisture, reducing humidity.

Another way to lower humidity is with desiccants. Desiccants rely on media that comes in contact with the air causing solid heat absorbance and liquid absorbance, which removes moisture from the air without changing the temperature.

Implementing controls

These methods for dehumidification can happen in many ways, from building-wide measures to location-specific and even portable methods.

Controlling humidity can be challenging. Staying within seasonal zones may require a specific strategy or a combination of strategies. Cold coil or desiccants are two approaches that can be effective. Dehumidification tactics can be implemented on a variety of levels, including whole-building methods and location-specific options for trouble areas.

Regardless of strategy, improving humidity leads to safer, more comfortable and more productive occupants. Understanding humidity and its effect on the overall IEQ of your building can pay big dividends for your business.