1. Increase the hot air flow or temperature of melt blown electret (increase the fineness of fiber, reduce the porosity, improve the catching ability, but increase the resistance).

　　2. Increase the electrostatic voltage (current) (polarization fiber, increase the electrostatic field energy of fiber, improve its adsorption capacity).

　　3. Adding powder or other electrets into the raw materials (improving the power receiving ability and storage time of the fiber, making the fiber carry more charge and charge time).

　　4. Increase the net bottom suction (increase the density of fiber, improve the catching ability of fiber). Large gram weight is obvious, not commonly used).

　　5. Reduce the output properly (with the same process, the extrusion volume becomes smaller, the fiber becomes thinner, and the resistance increases).

　　6. Increase the working temperature of die head (die tip) and other areas (better melt fluidity and thinner fiber).

　　7. Increase the spinning environment temperature (the fiber becomes thinner, generally when the room temperature rises, the resistance increases obviously, and other physical indexes decrease).

　　8. Increase the amount of electret powder properly.