What is the first action an operator should take before traveling under a low pipe rack?

The first action an operator should take before traveling under a low pipe rack is to post a signalperson to check clearances. This step is crucial because it ensures that the operator has an additional set of eyes to assess whether there is enough vertical clearance to safely pass under the obstruction. A signalperson can provide real-time feedback on the situation, helping to prevent accidents or damage by confirming that the crane's height and configuration are suitable for the space available.

Communicating with the crew, while important, does not directly address the immediate need to ascertain if the crane can pass safely under the pipe rack. Lowering the crane might seem like a solution, but it does not guarantee that the clearance will be appropriate; it’s essential to first verify the heights relative to the structure. Similarly, proceeding with caution without a thorough assessment of the clearances could lead to dangerous situations if the operator misjudges the height. Hence, having a signalperson dedicated to checking clearances is the safest and most effective initial action to take in this scenario.