Misleveled cars are one of the most common causes of elevator related injury. An elevator is considered misleveled if the elevator floor (car sill) is not level with the landing floor, creating a trip hazard for passengers who are accessing and egressing the elevator.
In this article, elevator expert and industry veteran Michael Vallone discusses the factors that contribute to elevators becoming misleveled, the maintenance requirements for typical elevator types, and relevant industry standards.
Elevator Leveling - Expert Overview
The automatic landing system on an elevator controls where the elevator stops at each floor. Whether the elevator system utilizes geared or gearless traction or hydraulic lifting technology, all elevators incorporate a landing system that controls the leveling of the elevator. The landing system technology used will vary based on the age, application type and the speed of the elevator. The landing technology may include systems that utilize switches or magnets in the hoistway, or selectors in the machine room driven by cables or tapes.
Elevator Maintenance Requirements
Without adequate periodic maintenance and adjustment any type of landing system may experience failures that can cause an elevator to mislevel. The following factors can all affect the leveling of an elevator:
- Equipment age, condition, and accumulated wear
- Design and quality of the equipment
- Environmental Conditions
Elevators of an older technological vintage generally require maintenance to be performed more frequently to assure proper leveling function. Older equipment such as those types that utilize motor-generator sets may require monthly maintenance at a minimum to achieve this goal. Consistent monitoring of the commutator condition and the motor-generator brushes is necessary to maintain the proper voltage to the hoist motor. The failure to properly regulate the voltage from the generator to the motor is one means by which erratic operation and misleveling of the elevator can occur.
Misleveled Elevators are Known Hazards
A misleveled elevator creates a dangerous condition that is well known within the elevator industry. Statistics demonstrate that misleveling accounts for approximately 25% of the recordable elevator incidents. Elevator technicians are trained to adjust elevator leveling to a zero tolerance in recognition that any misleveling of an elevator can create a hazardous tripping condition. Various types of maintenance and adjustment procedures may be required in order to minimize or eliminate these hazardous conditions.
Geared and gearless traction elevators that utilize landing systems such as mechanical selectors may require an increased frequency in the performance of maintenance due to the amount of moving components in operation. Other forms of landing systems such as perforated and/or magnetic tape systems may require maintenance and adjustment procedures unique to the specific equipment utilized. Factors that may impact leveling on hydraulic elevators may include improper valve adjustment and excessive oil temperatures.
Standards for Elevator Maintenance and Safety
ASME A17.1 Safety Code for Elevators and Escalators is a standard for elevator design, maintenance and operation. Safety codes and standards, including the A17.1, are intended to enhance public health and safety. The Code contains sections which outline the maintenance, repair, and replacement requirements for both new and existing elevators, and clarifies that the maintenance intervals should be specific to the particular equipment in the building. Our experts can help to determine which standards and local codes are relevant to your case.
Elevator Maintenance Agreements
The individual maintenance requirements for each specific type of elevator system should be taken into account when considering a maintenance agreement. This decision should also be based upon the original equipment manufacturers (OEM) recommendations for the particular type of equipment involved. If the maintenance frequency is inadequate, the elevator may develop leveling issues due to insufficient or inadequately performed maintenance. Our experts commonly analyze maintenance agreements in the course of their investigations to determine if the frequency and thoroughness of maintenance was appropriate for the equipment and anticipated usage.
Elevator Safety Investigations
The Elevator and Escalator experts at Robson Forensic have the necessary training, education and experience to investigate a broad range of mishaps involving elevators, escalators and other forms of vertical transportation equipment encompassed under the A17.1 and associated Safety Codes. Our elevator and escalator experts are industry veterans who have worked for manufacturers, installation contractors, and maintenance companies. They understand how this specialized equipment is designed to function and can reliably identify if a malfunction in a landing system or other associated system component contributed to the injury or loss in your case.
For more information, submit an inquiry or contact the author of this article.
Elevator & Escalator Expert
Michael Vallone is an elevator and escalator expert with nearly 20 years of industry experience as a field mechanic, maintenance supervisor, and operations manager. He has direct experience as a mechanic and supervisor of mechanics for new installations of low-rise hydraulic and machine-room-less to high-rise geared and gearless traction elevators. He also has significant hands-on experience as a qualified conveyance mechanic and supervisor of mechanics performing maintenance, service, and repair across many different models and vintages of elevators and escalators. He is a National Association of Elevator Safety Authorities – QEI-1 Certified Elevator Inspector as well as a Certified Elevator Mechanic through the National Elevator Industry Education Program.