In the National Electrical Code, what do the terms 'shall' or 'shall not' signify?

In the National Electrical Code (NEC), the terms 'shall' or 'shall not' are used to indicate mandatory rules that must be followed. When the code specifies that something 'shall' be done, it establishes a requirement that is essential for compliance with safety standards and regulations. Therefore, adhering to these directives is crucial for ensuring safety, reliability, and consistency in electrical installations.

This language helps ensure that electrical work meets the minimum safety and performance standards designed to protect life and property. Failing to follow these mandatory requirements can lead to significant safety hazards, including fire risks or electrical shock. As a result, the terminology used in the NEC emphasizes the importance of compliance with these rules rather than treating them as mere suggestions or guidelines.