Many accidents including large disasters are triggered by electrostatic discharge. Human lives and billions of dollars in property damage are lost every year, mainly due to the unobtrusive condition of electrostatic charge: it is not detected by human vision and other senses, as opposed for instance to mass and temperature. Accumulated charge in any portion of matter is hardly perceptible without suitable instrumentation. Electrified materials may appear harmless and safe to the naked eye, even when they are storing large amounts of charge, approaching the dielectric breakdown limits. For this reason, safety codes for the avoidance of hazards due to static electricity are very important and they are constantly updated in industrial environments. This chapter describes situations where electrostatic charge is a safety concern together with protective measures, discussing them with the help of recent knowledge on charging mechanisms and charge stability in various systems.