EMP Packs, Dr. Xu's Subdermal Tools and the program Fool deal EMP damage to their targets. EMP damage reboots mainframe devices, permanently disables guards' Heart Monitors, and destroys EMP vulnerable drones.
Devices with Magnetic Reinforcements and more than 2 firewalls are protected against EMP damage; EMP damage breaks 2 of their firewalls instead of rebooting or destroying them.