Escalator installation is performed by specialized contractors at heights and angles specified by the manufacturer. The escalator unit is heavy (several tons) and requires careful planning for delivery, positioning, and installation. Structural supports must be designed to carry the escalator load plus live loads from passengers. Structural supports typically include a framework supporting the escalator unit in a rigid manner. The escalator is positioned at the design angle (typically 30 to 35 degrees) and securely fastened to the supports. Electrical connections are made to provide power to the drive motor and control systems. Modern escalators have variable-frequency drives that adjust speed based on demand and allow gentler acceleration and deceleration. Safety devices including floor-level landing sensor switches prevent operation if objects are present at landings. Handrails must move smoothly at constant speed and must have proper tension. The steps and treads must be clean and free of debris that could cause slipping. Combs at the top and bottom of the escalator prevent passengers from becoming caught between the step and the fixed structure. Testing verifies all components function properly. Run-in testing operates the escalator continuously to verify bearing and mechanical systems. Load testing with weighted dummies verifies structural integrity. Regular maintenance is critical for safety; escalators should be inspected and maintained monthly by trained technicians. Common issues include handrail speed variation and step alignment.