A forklift speed limiter is any control that stops a truck exceeding a set travel speed: a throttle restriction on an internal-combustion truck, a programmed ceiling inside an electric truck’s controller, or a radar sign that lights up when the limit is broken. The categories are worth separating, because one family enforces and the other merely announces, and the difference shows up in the injury patterns this site publishes from the federal severe-injury dataset, 5,154 forklift-involved reports across 2015–2025.
The two families: alert and enforce
Radar speed alert systems announce. A radar unit mounted at the aisle or dock measures the speed of traffic passing it, up to 160 feet away on the Safe-Speed system in dealer catalogs, and lights a bright “SLOW DOWN” sign when a truck exceeds the limit you set, adjustable between 3 and 30 mph on that unit, with an optional buzzer. These systems cost the least and install without touching the truck, but they assume the operator responds to the sign. A driver who has learned the sign is empty theater, and drivers do learn that, will keep their foot down.
True limiters enforce. A retrofit throttle limiter sits between the pedal and the engine on gas or diesel trucks, restricts travel speed to the programmed ceiling, and, on the GLOBAIoT unit we tracked, applies the restriction only while the truck is moving so hydraulic lifting power is untouched, with limits adjustable between 6 and 30 km/h and a two-speed mode for different zones. On electric trucks the same outcome usually needs no new hardware: the dealer programs a maximum travel speed into the truck’s controller, which is often the cheapest option in the family. And zone-based speed control, where the truck slows itself inside marked areas, is the rung of collision avoidance that overlaps this category most closely, which is why the systems index keeps them in adjacent columns.
Does OSHA require a speed limiter?
No. The powered-industrial-truck standard, 29 CFR 1910.178, sets no numeric speed limit; it requires trucks to be operated in accordance with the employer’s rules and the conditions of the workplace, which leaves speed policy to the site. The practical reading, spelled out in our plain-English guide to 1910.178, is that the employer sets the limits, and a limiter is what turns a posted number into a physical fact instead of a hope. Our safety rules guide covers the speed physics, the stopping-distance math that makes walking-pace limits in shared zones arithmetic rather than conservatism.
What they cost
Planning ranges, not quotes, from the sources snapshotted for this guide. A radar speed alert sign lists around $2,100 per unit in the dealer catalog we tracked. Retrofit throttle limiters are priced per truck plus installation, and sites with mixed fleets should expect per-model engineering, because the harness differs between gas and diesel drivetrains. Controller-based speed programming on electric trucks is often a dealer software setting, frequently the lowest-cost path for an all-electric fleet. Whatever the family, the scope you send to vendors should pin the same three things: which trucks, which speed ceiling per zone, and who may change it, because the quote form forwards exactly that scope.
Where they work and where they quietly fail
Speed control fails socially, not electronically, the same way every warning layer does. A sign that chirps at every truck teaches operators to ignore it, which is why enforcement beats announcement in high-traffic aisles. A limiter that any mechanic can bypass with a jumper is decoration with a purchase order attached, so the bypass question belongs in the vendor conversation before the pilot, not after a complaint. And the maintenance half is mundane: sensors and displays need the same daily inspection pass as any other safety equipment, because a radar unit with a dead lamp protects nobody. Sites that put the limiter check in the pre-shift routine keep the control they paid for.
Speed control is one layer, not the whole program
A limiter reduces the severity of the struck-by and caught-between events that dominate the severe-injury narratives, but it does not detect a pedestrian behind racking, which is the job of detection systems. The defensible order is the one our Risk Scorer produces in two minutes: score the exposure, fit the enforcement layer the data points at, and compare the families on the systems index before asking for prices. Your state’s injury series provides the local context a budget meeting actually listens to, and every estimate here is labelled as such, a planning aid, not a compliance verdict.