What is one of the two most common reasons for activating an Emergency Shutdown Device (ESD)?

Activating an Emergency Shutdown Device (ESD) is a critical safety measure in power engineering, particularly when addressing hazardous conditions or potential equipment failures. One of the primary reasons for using an ESD is to shutdown and isolate rotating equipment.

When an ESD is activated for this purpose, it serves to quickly cease operations of the equipment in order to prevent further escalation of hazardous conditions, such as fires or explosions, which might arise from malfunctions. Isolating the equipment ensures that any potential leaks or spills can be managed safely, reducing risks to personnel and the environment. This approach enhances safety and allows for a more controlled and gradual approach to maintenance and emergency response.

While other options address various shutdown scenarios, they either do not fully encompass the urgency and safety focus of ESDs or do not align with the specific context of emergency situations, where isolation is a critical step to ensure safety and operational integrity.