Humidity is the amount of water vapor in the air, Depending on your local climate and season of the year the amount of humidity can vary from very low to very high, for most people a humidity levels between 40 and 50% are considered comfortable and healthy, while indoor humidity levels under 30% or Above 60% cause discomfort and create health risks to the occupants. Controlling the humidity in your home is key for a healthy and comfortable indoor environment.