Humidity is the measure of the amount of water vapor present in the air. Humidity is mostly calculated as Relative humidity. For industrial and medical environments relative humidity becomes an important factor. A rise or fall in the values of humidity, beyond threshold levels, can lead to malfunctioning of control systems, decomposition of chemicals used in manufacturing process, reduction of shelf life of food products, corrosion of electronic components, formation of condensation and errors in weather prediction systems. So, as a security and safety factor, measurement of humidity values is very important.