The main purpose of an Ionizer in an air purifier is to improve the CADR (Clean Air Delivery Rate) of the unit. Some Sunpentown products are equipped with a needle ionizer - which uses high voltage, low current electricity to create negative electrons. These electrons run up the length of a pointed spike (or needle), where they stream into the air and attach themselves to oxygen molecules. Electrons are negatively charged and these air molecules are now negative ions.

Negative ions occur naturally in the air we breathe and they are quite harmless. Negative ions attract airborne particles such as smoke, dust and pollen. When enough particles are attached to a negative ion, it becomes too heavy to float in the air and drops to the ground (a process known as agglomeration). Ionizers excel at removing these harmful, microscopic particles from the air providing health benefits.