Got Humidity Issues?

As a facilities manager you should be aware of your responsibilities surrounding Indoor Air Quality (IAQ) and appropriate temperatures. In 1992, the Workplace Health and Safety Regulations stipulated in regulation 7 that ‘During working hours, the temperature in all workplaces shall be reasonable’.

But why should temperature and humidity levels affect you? The simple answer is that employees working in conditions that are said to be below or above their thermal comfort levels can suffer from potential health problems and be less productive. As a facilities manager it will most likely be your responsibility to ensure that this does not happen.

There have been many suggestions and inventions designed to regulate and improve office humidity levels but the simple and most effective way can be seen in the introduction of office plants. This article looks at how planted office displays can prevent facilities managers from feeling the heat and the studies that have proved it.

Humidity is the measure of water that air will hold and is more commonly referred to as Relative Humidity (RH) as it is measured relative to temperature. It is measured in this way due to the direct relation between the two. For example, the warmer the air the more humid it will be as warm air can hold more water.

It is often easy to tell when indoor air is more humid than outdoor air as it will condense when it meets a colder surface causing condensation on office windows and doors. But how can office plants reduce humidity?

The humidity levels inside plants are close to 100% and are maintained through the plants natural transpiration process through tiny pores, called stomata, in their leaves. Office plants inhale Carbon Dioxide through these pores and exhale oxygen and water. In terms of relative humidity, the temperature of a room determines how much moisture a plant will exhale.

The cold dry air in most modern offices force office plants to exhale moisture as water always moves from high to low humidity. Many academics have since studied the effect of office plants and humidity levels in order to determine how useful plants are at regulating the overall humidity of an office building.

In a study conducted by Dr. Virginia Lohr at the Washington State University the results of an investigation of the relationship between office plants and humidity levels showed that plant transpiration in an office environment creates a humidity level exactly matching the recommended human comfort range of 30% to 60%.

Obtaining the right humidity levels in any building should be of paramount importance to any facilities manager as extremely high or low humidity levels can cause numerous health problems for employees working in that particular building. When the air inside a building is too dry, for example, employees may become vulnerable to colds and flu like symptoms.

Lohr found that through the natural transpiration and evaporation processes, office plants were able to add moisture to air that was too dry yet regulate themselves enough to ensure that no extra moisture was added to already moist environments. The study proved conclusive when the relative humidity in the offices without plants fell below the recommended 30% - 60% level.

When it comes to reducing humidity levels in office buildings then managers could do a lot worse than installing some planted office displays, what’s more plants for offices can also boost productivity and create a more aesthetically pleasing environment too.