When a tugger is mounted where the operator can NOT see the load, the signal person MUST use:

The requirement for a signal person to use signals that are standard for cranes when the operator cannot see the load stems from the need for clear and effective communication in environments where visibility is compromised. Signals used for cranes are universally understood, providing a reliable method for directing the movements of heavy loads safely. This is essential because it ensures that the operator and the signal person are on the same page regarding the lift operations, reducing the risk of accidents or miscommunication.

The use of standardized signals, which may include hand signals or radio communication, helps maintain safety and efficiency, especially in complex lifting scenarios where the operator's situational awareness is limited. The signals must be clear, concise, and recognized across the industry to facilitate an effective response from the operator.

In contrast, tugger type signals or aggressive signals would not be appropriate for this context. Tugger signals might not be universally recognized, and aggressive signals can create confusion rather than clarity. Thus, relying on established crane signals provides the best framework for ensuring safety and effectiveness when the operator's visibility of the load is impaired.