Escalator balustrades are primarily designed to: 

Explanation:

Safety Barrier: The primary purpose of the balustrade is to serve as a physical barrier between the user and the open space around the escalator. It prevents users from accidentally stepping off the sides or falling over.

1. Handrail Support: The moving handrail is mounted on top of the balustrade, giving users something to hold onto for balance while riding the escalator.

2. User Guidance: The transparent or semi-transparent balustrade panels help visually guide users on where the edge of the escalator is.

Additional Information In escalators, the balustrade is the side structure that runs along both sides of the moving steps. It consists of:

• A handrail (usually rubber or synthetic)

• Inner and outer panels (often made of glass, plastic, or metal)

• Support structure (to hold everything in place)

Functions:

1. Safety
   The most critical function is to prevent users from falling off the side of the escalator. Especially in crowded areas or where children and elderly people use escalators, the balustrade adds an essential safety element.

2. Support for Handrails
   The balustrade houses the mechanical path for the moving handrails, which synchronize with the escalator steps to help users maintain balance.

3. Aesthetic and Functional Design
   While aesthetics (Option 3) are considered, they are secondary to safety. Modern designs often feature sleek glass panels for a clean look, but the structural goal remains safety and usability.

4. Protection of Internal Components
   Balustrades also shield the internal mechanical systems from tampering or accidental contact, though they do not house control panels (Option 4). Control systems are usually located within the machine room or under the landing platforms.

5. Not Meant to Support Step Weight
   The steps and their supporting tracks are independently housed in the truss section of the escalator, not in the balustrade (eliminating Option 2).