The Back and Material Handling Issues

The Spinal Column Cervical Thoracic Lumbar

The Basic Structure

Epidemiology of Back Injuries Short Term or acute effects: Sharp Surfaces Dropped Material Struck-by Moving Materials Mechanical Stress Slips and Falls “Simpler” Cause and effect relationship

Epidemiology Chronic or Long Term Effects Back Ache or Pain Disc Degeneration Cause and effect not as simple, more difficult to analyze

Return to Work Out more than 6 months only 50% chance of returning One year only 25% Management and Practitioner Training One study showed that claims dropped from 200K to 20K per year by providing modified work and conservative treat

Material Handling Lifting/Lowering Pushing/Pulling Carrying Weights and Forces Frequency of Activities Load Center of Gravity

Material Handling

Job Risk Factors Weight of the Object Location (position of load w.r.t. worker) Frequency of Lifts Stability of the Load Hand Coupling Workplace Geometry Twisting/Stooping Environmental Factors

Personal Risk Factors Gender Age Anthropometry Lift technique Attitude Strength Training

Examples of Manual Handling Controls Avoid extreme range of motion when lifting Redesign work station/work area to allow freedom of movement Provide handles on material handling equipment Provide lift-assist devices and tables Unit Load Concept

Job Design Can reduce one-third of compensable LBP Minimize reach and lift distances Keep off floor Work station design Frequency Relax time standard Rotation Work-Rest allowances

Job Design Minimize Weight Mechanical aids Carton capacity Balance contents Convert Carry to push/pull Push over pull Use large wheels

Training Focus on awareness and avoidance Get object as close to body as possible Planning Use of handling aids Back Schools Strength and fitness important

NIOSH Lifting Equation 1991 Version

NIOSH Lifting Equation Objective: Reduce occurrence of lifting-related LBP 1981 and 1991 equations 1981 limited to sagittal plane 1991 includes asymmetry and coupling

Disqualifiers for Use One handed lifts More than 8 hours Seated or kneeling Restricted work space Unstable Objects Carrying, pushing or pulling while lifting Wheelbarrows or shovels High speed motion Unreasonable foot/floor coupling Unfavorable environment

Definition of Terms RWL = Recommended weight limit LC = Load constant HM = Horizontal multiplier VM = Vertical multiplier DM = Distance multiplier AM = Asymmetric multiplier FM = Frequency multiplier CM = Coupling multiplier

RWL = LC x HM x VM x DM x AM x FM x CM 1991 Equation RWL = LC x HM x VM x DM x AM x FM x CM

1991 Guide Compare RWL to Actual Load (L) If Greater than or equal to 1 problem

Lifting Index L RWL

1991 Multipliers LC = 51 Pounds HM = 10/H VM = 1-.0075 x / V-30/ DM = .82 + (1.8/D) AM = 1 – (.0032 x A) FM go to Table CM go to Table

NIOSH Worksheet

Lifting Example

NIOSH Workshop

NIOSH Workshop Start of Lift End of Lift

NIOSH 1991 Lifting Calculator

WISHA Calculator for Analyzing Lifting Operations

www.lni.wa.gov/wisha/ergo/calculator/ergo_workshopIE.htm

WISHA Workshop

WISHA If the job is a hazard Reduce weight of load Increase weight of load so that it requires mechanical assist Reduce the capacity of the container Etc.

References Applications guide for the revised NIOSH lifting equation – On CD Elements of Ergonomic Programs – On CD Musculoskeletal Disorders and Workplace Factors – On CD Work Practices Guide for Manual Lifting NIOSH 81-122 References continue on next slide

What does the worker need to know from this presentation?