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Lift tables are used to raise and position materials for a worker in such a way as to reduce
potential injuries in a wide array of industries. Lift tables are designed to impose proper
ergonomic principles into common work functions, and thus the selection process of this equipment
is very important to achieve the maximum benefit of their application.
By following the few basic steps outlined below, proper equipment selection can be easy to
understand and achieve.
Step 1: Identify the characteristics of the materials being handled. By answering the following
questions, you will be able to select the proper capacity, top size, and design of the table you
should acquire.
How heavy is the entire load that is in need of being positioned?
Models commonly support loads ranging from 1,000-6,000 lbs in 500 lb increments.
What are the dimensions of the entire load?
You will want to select a lift table top size that supports the majority of the load, while being
careful not to get a table too small for stability sake, or too large whereby the top may overhang
the load to such a degree as to force workers to have reach.
How will the load be placed on and off the equipment being selected?
If by forklift or conveyor, a standard lift table will be fine. However, if a pallet truck or other
floor level loading is required, a ground entry table or pit-mounted table must be used which will
increase cost significantly due to design characteristics and OSHA compliance.
If the load consists of individual items what is their weight and size?
The size of individual items is important in targeting how high the lift table must lift to provide
proper ergonomic positioning. Fundamentally, you will want the highest placement or the lowest
placement of an individual product to be as close to waist level as possible. The typical range
for standard lift tables are 24", 36" and 48" models with a lowered height of 6-8", this provides
a range of table heights from 6" to 54" to select from. In addition the heavier the individual
item is the more important it is that the item can be placed exactly at waist level and within
short reach of the operator to reduce strain.
Step 2: Identify what exposures to workplace injuries exist in the work area.
How often will the operator be required to lift a load?
The more items an operator handles the more likely RMI (repetitive motion injuries) are to occur.
Thus the more repetitions of a job task the more exacting you will want to be with ergonomically
correct placement. Electro-hydraulic lift tables typically provide the most exact product placement
versus weight sensitive lifts or pneumatic scissor lifts, which often neglect variability in
operator height or item dimensions, variable weights, and move inconsistently making it hard for
the operator to place the load correctly. Although, such lifts provide an ergonomic solution when
access to electricity is limited.
How far will an operator be required to reach to retrieve or place a load?
Reaching is considered by many experts to be as bad or worse than lifting as it pertains to
workplace injuries. The smaller individual items are, the more reaching that is typically involved.
Weight and distance are large concerns in this area, and many design variations of lift tables are
available to reduce such exposures. Load rotation is one of the most effective ways to address
reaching exposures, or if the load is conducive to such handling tilting tables can also provide
operators better access for item retrieval or placement.
How far will an operator be required to carry a load?
Keeping carrying distances short is also vital in eliminating injury exposures. To this end proper
placement of a lift table is very important, and most lift tables can be outfitted with mobility
options, such as casters, fork pockets or dolly's to help shorten significant transition distances.
For lighter weights, lift carts can provide the ergonomic benefits of a lift table in a mobile and
economic package.
Step 3: Identify the characteristics of where the work will be done.
Are their any special environmental variables that may effect the equipment?
Many lift tables can be made with stainless steel, special bearings, and power supplies to meet a
variety of industry specific environmental compliance standards.
What physical restrictions may hinder proper access to the equipment?
Typically a lift table will take up only slightly more space than the load it is handling.
However, certain design concepts may take significantly more floor space, which without proper
consideration can lead to additional hazards to the operator. If floor space is a major concern,
compact lift tables provide moderately sized platforms with minimal base sizes.
Where can operator controls be placed in the work area?
Pedestal mounted controls, foot controls, and magnetic backed control boxes are all useful options
to consider when selecting a lift table. Primarily you will want equipment controls to be in a
location that the operator can optimize for ergonomic benefit, and additionally negate any
potential tripping hazard.
What power supply is available in the work area?
Electro-hydraulic lift tables can be specified to run on single-phase 115 volt, 230 volt, or
three-phase voltages of 230 or 460. The initial stroke of lift tables often creates a high amp
draw as the equipment gains inertia, especially on higher capacity tables. Single-phase models
thus may require dedicated 20-30 amp circuits, while three-phase units will operate quite
efficiently and are recommended in high usage applications.
Step 4: How to select a lift table that will perform.
How is the basic table constructed?
If you have a light duty application or low usage, most tables will fit the bill quite nicely.
However, if you require a more industrial grade table, look for hallmarks such as fabricated
scissors arms (rather than tubular steel), all welded construction, and that the table meets or
exceeds the industries quality standard ANSI MH 29.1 enacted in 1994.
What components are preferable to other components?
High quality cam rollers, pivot pins and bearings can make or break a lift table. When selecting a
lift table give preference and scrutiny to these components as well as the duty cycle of the motor
that powers the table. The longer the duty cycle the better as far as motors go, and staying with
a quality manufacturer such as Baldor or Leeson is always preferred rather than a imported or
generic motor due to the rigorous demands tables often put on hydraulic pump motors throughout a
workday.
What components assist in extending the service life of a lift table?
Maintenance is the key here just like with any equipment. While some tables feature no maintenance
capabilities and just wear out, some do offer maintenance capabilities that can greatly extend
service life. Grease fittings on pivot points and cam rollers are crucial in extending the service
life of a lift table. In addition, having motors and controls easily accessible and separated can
be an important variable to examine. Some manufacturers have made modular power units that are not
directly serviceable which is also a significant concern in regards to service life to consider.
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