Due to the widespread use of computer equipment, electromagnetic protection of processed data is still an issue. Structurally modified commercial equipment is used to protect devices against this phenomenon. The acquisition costs of such modified devices are enormous. However, the market offers information devices with very low susceptibility to electromagnetic infiltration. Safe fonts are a new solution in the protection of sensitive information against electromagnetic infiltration processes. The use of safe fonts not only increases resistance to electromagnetic eavesdropping but also makes it impossible. These devices are computer printers that use a slat with hundreds of LEDs arranged in several rows during the process of photoconductor exposure. The solution in the form of safe fonts is a universal method that protects process information against electromagnetic penetration. Safe fonts are effective not only for printers with slat LED. The solution can also be used for the protection of analog standard VGA, digital standard DVI, and printers with one diode and two diode laser systems.