*Question E0A07:
What is meant by “100% tie-off” regarding tower safety?*  

*Correct Answer is  B: At least one lanyard attached to the tower at all times*  

### AI Response: (may contain errors)  

**Explanation:**

1. **Correct Answer: B - At least one lanyard attached to the tower at all times**

   - "100% tie-off" is a safety practice used in tower climbing to ensure that the climber is always secured to the tower. This means that at least one lanyard (a safety line) must be attached to the tower at all times. This practice is crucial for preventing falls and ensuring the climber's safety while working at heights.

2. **Why the other choices are incorrect:**

   - **Choice A: All loose ropes and guys secured to a fixed structure**
     - This choice refers to securing equipment, not the climber. While securing loose ropes and guys is important for safety, it does not address the climber's personal safety directly.

   - **Choice C: All tools secured to the climber’s harness**
     - Securing tools to the climber's harness is a good practice to prevent dropping tools, but it does not ensure the climber's safety in terms of fall protection.

   - **Choice D: All circuit breakers feeding power to the tower must be tied closed with tape, cable, or ties**
     - This choice is related to electrical safety, not fall protection. Tying off circuit breakers is a lockout/tagout procedure to prevent electrical hazards, not a method for securing a climber to a tower.

3. **Useful Rules of Thumb:**

   - Always maintain a connection to the tower with at least one lanyard when climbing or working on a tower.
   - Use a double lanyard system to ensure continuous attachment when moving between anchor points.

Understanding "100% tie-off" is essential for ensuring personal safety when working on towers, which is a critical aspect of tower climbing and maintenance.