When selecting lifelines for fall protection, two main categories are crucial: horizontal and vertical lifelines.

**1. Horizontal Lifelines:**
   - *Cable Systems:* Utilizes cables stretched between anchor points, ideal for horizontal movement on surfaces like roofs or bridges.
   - *Flexible Lifelines:* Incorporates flexible materials such as synthetic ropes or webbing, providing adaptability to different work environments.

**2. Vertical Lifelines:**
   - *Rope Systems:* Features a vertical rope secured to anchor points, commonly used for ascending or descending in confined spaces or tower climbing.
   - *Ladder Climbing Systems:* Ensures continuous attachment along fixed ladders, enhancing safety during ascent or descent.

Selecting between horizontal and vertical lifelines depends on the specific requirements of the work. Considerations include the nature of movement needed, the structure of the work environment, and compliance with safety standards. Regular inspection and maintenance are vital to ensure the ongoing effectiveness of these lifelines in fall protection systems.