🔍 Key Concepts

• Standard crane hand signals used on U.S. waterfronts (often based on ANSI/ASME charts) • The difference between signals for hoisting/lowering the load vs raising/lowering the boom • How thumb direction and finger motion are combined to indicate two simultaneous crane actions

💭 Think About

• First, recall: what simple hand signal usually tells the operator just to raise or lower the boom? How is the thumb used in that signal? • Next, think: what additional hand motion is normally used to tell the operator to hoist (move the load up) or lower (move the load down)? • Now, combine them: with the arm extended and thumb pointing down, and the fingers flexing in and out, which action is the thumb telling the operator to do with the boom, and which action are the fingers telling the operator to do with the load?

✅ Before You Answer

• Verify what thumb up vs thumb down means specifically for the boom, not the load • Verify what flexing fingers in and out (as if beckoning) means for the load direction (up or down) • Confirm that the chosen option reflects two simultaneous actions: one on the boom and one on the load, both consistent with the standard meanings above