Which type of control should not be part of the manual actuation means?

The correct choice highlights that electrical control should not be part of the manual actuation means for dry chemical extinguishing systems as defined by the NFPA 17 standards. Manual actuation means are designed to allow operators to activate the extinguishing system directly, relying on human intervention without any intermediary processes that could fail or malfunction.

Mechanical and manual controls are inherently designed for direct human operation, ensuring immediate response in emergencies. These methods can be pulling a lever, pressing a button, or initiating another direct manual intervention that does not depend on electrical systems.

Hybrid control combines aspects of both manual and automatic control, but it still prioritizes manual input, making it suitable in certain contexts of emergency response. By avoiding the inclusion of electrical control, the system maintains reliability and simplicity, focusing primarily on the operator's ability to act decisively without the potential interruptions that electrical systems might introduce.