Reference library

Elevator & Escalator Glossary

Plain-English definitions for the terms you'll actually hear on the job or in a building manager's meeting — no code-book language.

Read this first. These are working definitions for everyday use on the job, not legal text — for the exact, binding wording of any term, check the code edition your jurisdiction has adopted (see Find your code). Last verified: 25 July 2026.

A

ADA

Americans with Disabilities Act. Drives requirements like control-button height, audible floor/direction signals, and door-timing that affect accessibility compliance for building owners.

Anti-slide device

A raised guard on an escalator balustrade skirt or handrail area meant to discourage riders from sliding down the outside of the unit.

B

Balustrade

The full enclosing side structure of an escalator or moving walk — skirt panel, decking, newel, and handrail together.

Buffer

A spring or oil-filled device at the bottom of the pit that absorbs impact if the car or counterweight ever overtravels past its normal limit.

C

Car

The compartment (cab) that carries passengers or freight up and down the hoistway.

Car call

A destination-floor button pressed from inside the car, as opposed to a hall call made from a landing.

CAT1 / CAT5

Categorized safety tests required at set intervals (roughly annual for CAT1, roughly every five years for CAT5) — more rigorous, equipment-down testing that costs a building real downtime and money.

Comb plate

The toothed plate at the top and bottom of an escalator where the moving steps flatten out and mesh with fixed teeth — the point most "shoe caught in escalator" incidents happen.

Compensation chain / cable

Heavy chain or cable hung below the car and counterweight on taller rises to offset the changing weight of the hoist ropes as the car travels.

Controller

The control system that governs dispatching, speed, and floor leveling — the "brain" of the elevator.

Counterweight

A weight connected to the car by ropes over the sheave, roughly balancing the car's weight so the machine only has to lift the difference.

D

Destination dispatch

A lobby system where riders enter their destination floor before boarding, letting the controller group people heading to the same floors into the same car to cut wait and ride time.

Door interlock

A safety device that mechanically prevents the car from moving unless both the car door and the landing door are fully closed and locked.

E

Entrapment

An incident where a passenger is stuck inside a stalled car — distinct from an injury; most entrapments resolve with no one hurt.

F

Fireman's service (Phase I / Phase II recall)

An emergency operating mode: Phase I automatically recalls cars to a designated floor when smoke/fire is detected; Phase II lets firefighters take manual in-car control once on scene.

Full-service contract

A maintenance contract covering both labour and parts for repairs, as opposed to an oil-and-grease contract that only covers routine lubrication and inspection.

G

Governor (overspeed governor)

A device that monitors car speed and triggers the safety gear to grip the guide rails if the car ever exceeds its rated overspeed threshold.

Guide rail

The vertical steel rail running the height of the hoistway that keeps the car and counterweight travelling in a straight line.

H

Hall call

The up/down button pressed at a landing to request a car, as opposed to a car call made inside the cab.

Handrail

The moving rail escalator and moving-walk riders hold, synchronized to travel at the same speed as the steps or pallets.

Hoistway

The vertical shaft the elevator car and counterweight travel through, floor to floor.

Hydraulic elevator

An elevator lifted by a fluid-driven piston (plunger) rather than ropes over a sheave — common in low-rise buildings.

I

Interlock

See Door interlock.

J

Jamb

The vertical frame piece on either side of a landing door opening.

L

Landing

A floor stop — where the car aligns with a building floor and the doors open.

Leveling

The automatic fine-adjustment that lines the car floor up flush with the landing floor before the doors open.

Load-weighing device

A sensor that measures how much weight is in the car, used to bypass hall calls when full or detect an overload condition.

M

Machine room (MR) / Machine-room-less (MRL)

A traditional elevator has a dedicated room housing the hoist machine and controller; an MRL design fits that equipment into the hoistway or a control cabinet instead, freeing up building space.

Modernization

A comprehensive upgrade of an aging elevator's major components (controller, machine, wiring, fixtures) — a capital project, not routine maintenance.

Moving walk (travolator)

A horizontal or gently inclined conveyor for pedestrians, using pallets instead of an escalator's stepped treads.

N

Newel

The rounded end section of an escalator balustrade, at the top and bottom, where the handrail wraps around before disappearing into the newel guard.

O

Oil-and-grease contract

A minimal maintenance contract covering routine lubrication and inspection only — repairs and parts are billed separately, unlike a full-service contract.

Overspeed governor

See Governor.

P

Pallet

The individual flat tread unit of a moving walk — the moving-walk equivalent of an escalator's stepped "step."

Pit

The space below the lowest landing where the car travels when at its lowest point, housing the buffers.

Q

QEI

Qualified Elevator Inspector — the certification (to ASME QEI-1) held by inspectors who test equipment for code compliance. See the Industry Associations guide for who certifies QEIs.

R

Recall

Automatically sending a car to a designated floor in response to an event — fire alarm, power failure, or an emergency-power condition.

Regenerative drive

A motor drive that feeds braking energy (e.g., a descending loaded car) back into the building's electrical grid instead of dissipating it as heat — an energy-efficiency feature buildings are increasingly asking for.

Rope (hoist rope)

The steel wire ropes that suspend the car and counterweight over the sheave in a traction elevator.

S

Safety gear

A mechanical device on the car (and sometimes counterweight) that clamps onto the guide rails to stop it if the governor detects overspeed or a free-fall condition.

Selector

The device (older units use a mechanical tape/wheel; modern units use encoders) that tracks the car's exact position in the hoistway for leveling and dispatch.

Sheave

The large grooved pulley wheel the hoist ropes run over, driven by the machine.

Sill

The threshold plate at a car or landing doorway that the doors slide across.

Skirt panel

The vertical panel running alongside an escalator's steps, between the steps and the balustrade decking.

Step

The individual moving tread unit of an escalator, with grooves that mesh with the comb plate at each end.

T

Traction elevator

An elevator driven by friction between the hoist ropes and a motor-driven sheave, rather than a hydraulic piston — the standard design for mid- and high-rise buildings.

Truss

The structural steel frame that supports an escalator's entire mechanism between its top and bottom landings.

V

VVVF (Variable Voltage Variable Frequency)

A motor drive technology that varies both voltage and frequency to give smooth, precise control over acceleration, speed, and deceleration.

Want the manufacturer side of the picture? The OEM Family Tree covers who owns who among the major brands whose equipment you'll see these terms applied to.

See the OEM family tree →

← Back to the library

Want these terms in context, on the job?

Escalator Field Command's Field Guide covers the code chapter by chapter, in the same plain English — searchable and offline.