Active Systems

“Active mitigation system is equipment, devices, or technologies that need human, mechanical, or other energy input to function. An example is an automatic shutoff valve that limits the duration of a hazardous material release.”

Reference: Walter, R. J. (2010). Local Emergency Planning Committee Guidebook: Understanding the EPA Risk Management Program Rule: Wiley. [Retrieved on October-12-2015]

Note: An active system is formed by a loop consisting of a sensor, a processor and an actuator. Full protection is expected from high integrity systems. These are active and highly reliable, they do not contain a human-in-the-loop, and are called Safety Instrumented System. According to standard IEC 61511 there are three Safety Integrity Levels (SILs): 10-1-10-2; 10-2-10-3; 10-3-10-4