Which sign must adhere to specified exact wording for safety?

The "Warning, No Lifeguard on Duty" sign must adhere to specified exact wording to ensure clarity and compliance with safety regulations. This sign is crucial because it informs users about the absence of professional supervision, which directly impacts their safety while using the pool facilities. The standardized wording helps ensure that everyone understands the significance of the message, promoting awareness and encouraging individuals to take personal responsibility for their safety and that of their companions.

Uniformity in signs like this is vital because it provides a consistent message across different facilities, which aids in preventing accidents that might occur due to misunderstandings regarding the availability of lifeguard services. In contrast, other signs, while they may still be important for safety, do not typically carry the same regulatory requirement for specific wording.