Deborah Lechner, PT, MS

Basic Physical Demands Scaling

Scales Vary by Category of Physical Demands

Categories/ Dimensions Examples

Manual Materials Handling

Position Tolerance (static postures)

Mobility/Movement and Repetitive Motions

Hand FunctionBalanceCoordination

Lift, carry, push, pullSit, stand, stoop,

crouch, reach, kneel Walk, crawl, climb,

stoop, crouch, reachHandling, fingering,

grippingStatic, dynamic Bilateral, eye-hand-

foot, eye-hand, eye-foot

Possible Scales for Physical Demands

Manual Materials HandlingWeight/force handled (lbs/N)Size and shape of object Handles vs. WithoutBilateral vs. UnilateralVertical height of lift Distance of lift

Manual Materials HandlingCan occur in any position & combined with

a variety trunk movement (i.e. bend and rotate while lifting)Lift/Lower – height, position of load and relationship to

body – horizontal distance from loadUnilateralBilateral

CarryUnilateralBilateral

Push/PullUnilateralBilateralWhile whole body is moving

Possible Scales for Physical Demands

Non-Materials HandlingPosture/Positions maintained

Duration (hr, min, sec, % day)Continuous duration (hr, min, sec)Intensity (degrees of position, range of motion,

WNL, min, moderate, severe)Balanced/Symmetrical

Mobility/Ambulation (walk, crawl, climb, run)DistanceRepetitionsSpeedDuration (% of day)

Possible Scales for Physical Demands

Non-Materials handling (cont’d)Repetitive movements (squatting,

reaching, stooping)RepetitionsFrequency Cycle timeDuration (% of day)Continuous durationIntensity (degrees of position, range of

motion, WNL, min, moderate, severe)Balanced/Symmetrical

Scales for BalanceDynamic vs. staticDuration (% of job required)Surface Type

Even surfaceUneven surfaceClimbing (stairs, ladders, poles)Beam and scaffolding/narrow ledges

Surface ConditionsWet vs. dryIce, snowOil

Possible Scales for Hand Function

DurationRepetitionCycle timeGrip strength (lbs)Whole hand vs. individual finger motionOne-handed vs. two-handedLevel of dexterity/coordination/speed

Combined Postures vs. Individual Joint Positions

• Squat/crouchingvs

• Spine flexion• Hip flexion• Knee flexion• Ankle dorsiflexion

• Ability to change position i.e. driving for required distance before stopping, viewing computer monitor and using keyboard for specific periods of time without rest

Simultaneous MotionMotions/Positions happen simultaneously – i.e. Squat

while looking down and reaching while handling. Or sitting on window sill while leaning, holding himself with one arm and reaching with another. NeckTrunkUpper extremities

ShoulderElbowHands

Lower extremitiesHipsKneesAnkles

Correlation to Tasks• Housekeeping (Light to Heavy)

Wet mopping the floorCleaning patient rooms after discharge

• Carpenter (Light to V Heavy)Erects framework for structures and lays subflooringBuilds stairs and lays out and installs partitions and cabinet work.

• Physical Demands:• Walking• Lifting• Pushing • Pulling

• Joint Angle Excursions• Flexion, Extension, rotation, abduction, adduction• Neutral vs. Non-Neutral• Joint angle excursions

How much detail????Challenge to balance level of detail vs.

feasibility of data collection

Current DOT MMH ScalingDefined in DOT, SCO, & COJClassifies manual materials handling demands:

Occasional Frequent (50%) Constant (20%)

Very Heavy > 100 lb. > 50 lb

> 20 lbHeavy 51 - 100 lb. 25 – 50 lb 10 – 20 lbMedium 21 - 50 lb. 10 -25 1 - 10Light 11-20 lb. 1 - 10 *Sedentary 1 -10 lb. * *

* negligible weight

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Current DOT Duration Scaling

Non-materials handling tasks classified according to duration of demand within the work day

Constantly 2/3 to the full dayFrequently 1/3 to 2/3 of dayOccasionally up to 1/3 of dayNever not required

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Current DOT Dexterity & Coordination Scaling

Dexterity Demands

Classified as an aptitude by the DOTRated on a 1 -5 scale

1 = top 10% of population2 = highest 1/3, exclusive of top 10%3 = middle 1/34 = lowest 1/3, exclusive of bottom 10%5 = lowest 10% of population

Grip Strength not addressedKeyboarding not addressedDuration address through C,F,O,N

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Types of Items & Associated Scales

Type Definition Examples

Cross-Job Relative General work activities - designed to apply to many jobs

Analyze, Calculate, Classify, Climb, Compute, Coordinate, Direct, Evaluate, Inspect, Lift, Monitor, Observe, Stand, Walk

Within-Job Relative Tasks Classic “Verb, Object, Purpose”Designed to be organizationally specific; easily used for HR activities like training

Qualitative Highly abstract, create no quantitative data

Narrative Job Descriptions,Job titles only

Types of ScalesType Scales Examples

Cross-Job Relative Absolute frequency, weight, absolute duration

Hourly, daily, weekly, monthly, quarterly<10 lbs., 11 – 20 lbs., >20 lbs.0 – 15 min, 16 – 30 min, 30 – 45 minDichotomous : Performed/Not Performed

Within-Job Relative Relative/% time spent, relative importance

¼ of the time, ½ of the time, ¾ of the time10%, 20%, 100%Not Important, Somewhat Important, Very Important

Qualitative No numerical ratings, No comparisons of jobs possible

Narrative Job Descriptions, Simple lists of tasks