Manual Handling in the Manufacturing Industry - Business.govt.nz

Manual Handling IN THE MANUFACTURING INDUSTRY

Published by the OccupationalSafety and Health Service of theDepartment of Labour,Wellington, New ZealandAugust 1991ISBN-0-477-03488-8AcknowledgementThis booklet has been sourcedfrom material provided by theOccupational Safety and HealthDivision of the Department ofLabour, Victoria.P198/10,000/19912

Introduction"Manufacturing" covers a widerange of industries including:textiles, clothing, footwear, motorvehicle assembly, food processing,pulp and paper, wood productsand metal products.The most common manualhandling injuries that occur inmanufacturing industries are:sprains and strains, back injuries,foot injuries and abdominalhernias. Back pain is a commonexperience. It can be caused oraggravated by manual handlingactivities at work, and bodypostures that are adopted duringwork.This booklet aims to help thosepeople with little or nooccupational health expertise toidentify manual handling problemsand prevent injuries. Using theapproach set out in the detailedpublication, Manual Handling:Guidelines for the Workplace, itgives practical advice and showsthrough examples how manualhandling risks can be first beidentified, then assessed andcontrolled in manufacturingindustries.3

Assessing manualhandling tasksThis booklet follows the approach for identifying, assessing andcontrolling manual handling risks that is set out in the publicationManual Handling: Guidelines for the Workplace. The approach issummarised by the diagram below, but it should be remembered that bothemployers and employees need to think about manual handling risks forpractical solutions to be found.Identifyrisks by consultationbetween employer andemployees (or theirrepresentatives).This checklist from theGuidelines will help:Assessrisks and set prioritiesaccording to need and therange of solutionsavailable.› ›This worksheet from theGuidelines will help:Controlrisks by:Redesigning oreliminating the job/task;Mechanical aids; orTraining and education.The worksheets from theGuidelines will help:››Review and evaluateIs the solution working?DesignAny initial or ongoing design should consider manual handling risks.›5

Risk identificationMake yourself aware of potential manual handling problems by askingthe following questions.1. Is the work strenuous?2. Does anyone have to lift, carry, push or pull heavy or awkwardloads?3. Are mechanical aids, e.g. lifting equipment, readily available andbeing used?4. Can the system of work (job design) be improved, e.g. workloadspread evenly throughout the shift; heavy, tiring tasks alternated withlight tasks?5. Is lifting done at waist level, or is it high or low?6. Are the heaviest and/or most frequently used items stored at waistheight?7. Can the work layout be improved e.g. more storage space to relievecramped conditions?8. Is all the equipment maintained regularly and in good working order?9. What injuries or problems have already occurred in this area, thatmay be related to manual handling?l0. Is the workplace environment safe? e.g. are floor surfaces even andnon-slip, are pathways clear?11. What sort of training and education programmes are provided?6

Principles ofpreventing manualhandling injuries1. Reduce the amount of manual handling.2. Reduce the amount of bending, forward reaching, andtwisting in all tasks.3. Keep all equipment in good working order.4. Keep the work environment safe.5. Ensure that suitable training and education in manualhandling is provided for all staff.These five basic principles will:• Help you identify which manual handling tasks pose a risk to healthand safety (risk identification); and• Make you aware of some of the possible solutions to common manualhandling problems (risk control). Some examples of these principlesare illustrated in the following pages.7

Reduce the amountof manual handlingManual handling is more than just lifting. Manual handling includes:pushingpullingholdinglifting8

Example: Unloading cartonsBy increasing the size and weight of the load and mechanising, manualhandling can be reduced and productivity increased.Opening 24 cartons of acommodity with a knife.Using a forklift and tilting machineto lift and open a 1 tonne(1000 kg) container eliminates therepetitive manual handling and therisk of knife injury.Lifting 24 x 20 kg cartons from apallet and carrying them to thestorage bay.Lifting and moving the 1 tonnecontainer with a hand-operatedforklift, makes the job a lot lessstrenuous and reduces the timespent on unloading pallets.9

Example: Degreasing metal componentsLifting 30 kg baskets of metalcomponents and carrying them toand from a degreasing machine.Using a hoist to lift the baskets onto the roller conveyor, eliminatesthe heavy lifting.The conveyor is on an angle, so that the baskets can be slid easily overthe rollers to and from the degreasing machine.10

Job rotationJob rotation can be used to reduce the amount of manual handling thateach employee does throughout the work shift. Job rotation can helpprevent sprains and strains by providing employees with a change ofactivity.The ideal combination of jobs includes a variety of sitting, standing andwalking activities.Each employee does a singlerepetitive job over the whole workshift, e.g. an assembly task.Each employee has a variety ofjobs throughout the work shift, e.g.assembly, packing and machiningtasks.Each job is designed so that itincludes a variety of activities, e.g.1st class machinist • setting upmachine • loading machine •checking machine • inspecting parts• loading parts to be taken away.11

A drum lifter makes moving andemptying drums a lot easier andsafer.A drum tilting lever reduces theeffort required in up-ending filleddrums.Using a forklift to move a drumeliminates the manual handlingrequired.For bulk handling of liquids, acontainer system which istransported by forklift eliminatesthe manual handling of drums.13

Example: Unloading bags ofgranulesPlatformsHolding the 30 kg bag of granuleswhilst emptying the contentsslowly into a cooker.The platform is then raised. Theemployee stands on the steps andguides the granules but doesn'thave to hold the bag.14

LiftersA hydraulic or power-operatedlifter can be used to reduce theeffort of moving By adjusting theheight of the lifter, the bags can beslid across to the lifter, rather thanlifted.The lifter can act as a platform forholding the bags whilst thecontents are being emptied.Vacuum liftersVacuum lifters are commonly usedfor picking up awkward, heavyloads, and large flat sheets, e.g.metal, glass, chipboard.Unloading 40 kg bags from apallet.An electrically-operated vacuumlifter eliminates the heavy lifting.The mechanical arm is guided bythe employee.15

CounterbalancedequipmentEquipment that is heavy, or used continuously, can be counterbalanced toreduce the manual handling effort required, e.g. hose of the vacuumlifter, tools used on an assembly line.Irons used in the clothing industrycan be counterbalanced to reducethe effort of lifting themcontinuously.Tools that are used repetitively,such as drills and screwdrivers,can also be counterbalanced.16

HoistsEach ingredient is carried up the steps and fed in by hand.All the ingredients are put into a hopper which is lifted with a hoist andemptied by hand. This reduces the holding and carrying work required.17

Lifting magnetsMagnets can be a useful aid in the manual handling of metal products,which are generally heavy and have sharp edges. They are used widely insheet metal workshops, engineering workshops, the motor vehicleindustry and the scrap metal industry. They are particularly useful forlifting and stacking steel plate and metal sheets, which are large andawkward to carry.This magnet is used with a hoist,to lift one sheet or block of metalat a time from a stack.These magnetic handles aredesigned for lifting and movingsingle sheets of metal.This magnet is used together with a mobile crane to unload and transfermetal products up to 900 kg. It makes the job easier, safer and quicker.18

TurntablesLeaning over the pallet to load andunload boxes on the far side.A pallet hoop turntable allows thepallet to be rotated 360° andreducing the carrying or bendingrequired — also providing toespace, to allow the load to be keptcloser to the body.Products being assembled on a linefrequently need to be lifted andturned around.A rotating turntable on theassembly line, or rotating base onthe product, eliminates the need tolift, and the amount of bending andtwisting.19

Reduce the amountof bending, forwardreaching and twistingDesign of equipmentand workstationsThe design of equipment andworkstations dictates, to a greatextent, the work postures and workmethods required. Use ofequipment that requires prolongedbending and twisting posturesshould be avoided. Newequipment should ideally be testedand assessed by the employeesconcerned, prior to purchase.Professional ergonomic expertisemay also be required.Repetitive bending is required toempty components out of a crateand on to a conveyor belt.A spring-loaded base keeps thecomponents at a convenient height.A forklift loads the crate on to a“tipper” platform, and the “tipper”is then operated to keep thecomponents at waist height.20

Employees often think of a better or easier way to do a job. There aremany examples where, by working together within the organisation,employees and management have been able to come up with somesuccessful "in-house" solutions to manual handling problems.Packing a heavy welding machineon the floor.A custom-built frame attached tothe conveyor belt reduces theamount of lifting and bendingrequired.The drilling is done on an unstablesurface in an awkward position.A custom-built frame whichreduces the amount of holding andbending, forward reaching, andtwisting required.21

SeatingSitting for prolonged periods in awkward postures whilst engaged inmanual handling activities, e.g. inspection, light assembly tasks, can leadto back pain or aggravate an existing back problem. Good seating is oftenneglected in the manufacturing industry. Stools (kitchen-type) and castoutoffice chairs are frequently provided. These are inappropriate in mostcases because they are not the right height and do not offer good backsupport. The two most important features to look for in a chair are:height adjustability and a good lumbar (low back) support. Wherepossible, it is preferable for people to be able to change between sittingand standing postures as they wish.Sitting with a bent back on a stoolwhich does not provide any backsupport or adequate foot support.At this workstation the employee isable to change between sitting andstanding postures.Sitting with a bent back on akitchen-type chair which is too lowand does not provide adequate lowback support.22This chair is height adjustable andprovides good low back support.

Work layoutThis work layout requires forwardbending and reaching over theconveyor belt, as well as turning topack the product in boxes.When the work is close to the bodythe employee can sit or stand witha straight back.Inadequate leg room under theconveyor belt forces the employeeto sit side-on in a twisted position.Adequate leg room under theconveyor allows the employee tosit with a straight back.23

Get the work height right!The ideal work height depends on the activity. Generally, lifting shouldbe done in front of the body at between shoulder and mid-thigh height —to reduce the amount of bending and twisting of the back.When the work height is too high, aids such as steps, stools, platforms,ladders or stairs should be provided, to reduce backward bending andtwisting actions of the spine.24

When the work height is too low, aids such as tables, chairs, platformsand adjustable conveyor systems should be provided, to reduce theamount of forward bending and twisting of the back required.Scissor-lift platform and table.Height-adjustable conveyorsystem.25

Use a table.Use a chair.26

Working close to ground levelrequires bending and twisting, andcan be fatiguing.Using a small stool on castors —or a box — may reduce the effort,as well as the bending andtwisting.This inspection task involvesrepetitive forward reaching. Thereis static loading of the neck, armsand back.The forearm supports and the backsupport of the chair reduce thestatic loading, and reduce theamount of forward reachingrequired.27

StorageAll frequently used components should be stored within easy reach, i.e.within 400 mm of the body. When large numbers of components need tobe on hand, e.g. assembly tasks, then the method of storage needsconsideration.Wire, tubing and hose can be stored on reels and fixed at a convenientheight.A foot-operated conveyor systembrings the components up to aconvenient height.Components can be stored onrotating turntables.28

Keep all equipmentin good working orderUnexpected or forceful actions required due to faulty or poorlymaintained equipment can lead to strains and injuries. All equipmentshould be maintained on a regular basis and repaired promptly whennecessary.What are the maintenance proceduresat your workplace?Is equipment and machinery maintainedto a checklist?29

Keep the workenvironment safeSlips, trips and falls during manual handling activities can lead toserious injury. Uneven or slippery floor surfaces, trailing hoses andcords, and obstacles on the ground are common hazards. Pathways,access ways and work areas need to be marked and kept clear so thatcollisions can be avoided. Manual handling injuries can be avoided byregular maintenance and housekeeping procedures.Pushing a trolley over an uneven surface can require a forceful action.Torn floor coverings are also a tripping hazard.30

Provide suitableeducation and trainingEmployees should get appropriate education and training in manualhandling techniques so that they are able to choose the best technique foreach particular situation. Training and education is more than teachingpeople how to lift correctly. The broad aims of training and educationare:1. To ensure that each employee has the skills and knowledge to be ableto do their job safely.2. To ensure that each employee has an understanding of the principlesof back care and the prevention of injury, which is relevant to theirparticular situation.3. To ensure that each employee has an understanding of the manyfactors that can cause back pain and injury.4. To encourage each employee to take an active role in the preventionof manual handling injuries at work.Using mechanical aids when theyare available.Using the correct lifting methodwhen possible by: bending theknees, keeping the back straightand keeping the load close to thebody.31