SAFed Health and Safety Passport Scheme

Module 9 — Manual Handling and Musculoskeletal Issues

9.1       Introduction

This document forms one of a series of modules on various health and safety subjects that comprise the examinable material considered necessary for the award of the SAFed Health and Safety Passport.

When you have studied this module you should have acquired sufficient knowledge to be able to answer the questions detailed at the end of the module.  Upon satisfactory completion of all modules, you will be eligible to undertake the final assessment for the award of the SAFed Health and Safety Passport.

The SAFed Health and Safety Passport is issued to Engineer Surveyors by the Health and Safety Manager of their employing company upon satisfactory completion of the Safety Passport final assessment.

The award of the SAFed Health and Safety Passport provides evidence that the holder of the Passport has the appropriate knowledge and awareness in health and safety matters considered necessary for an Engineer Surveyor to undertake the duties for which they are authorised by their employing company.

The passport is valid for a maximum of three years.

9.2       Key Objectives

Having studied the module you should have an awareness of

·         Legislation applicable to Manual Handling

9.3       Legal Commentary

The Health and Safety laws, which cover this module, are:

·         The Manual Handling Operations Regulations 1992

9.4       Discussion — Manual Handling, what are the Hazards?

Lifting, pulling, pushing or in any other way moving or holding still any material or object by personnel, physical effort can cause injury to the person concerned.  More than a ¼ of the lost time accidents reported to the HSE are the result of injuries sustained during manual handling operations.  The most common injuries arising from manual handling are basically musculo-skeletal problems, “strained back” meaning any strain to muscles, ligaments or tendons.  The same then applies to shoulder, neck, arms, wrists, etc.

Reducing the Risk of injury

In considering the most appropriate controls, an ergonomic approach to designing the manual handling operation will optimise the health, safety and productivity associated with the task.  The task, the load, the working environment, individual capability and the inter-relationship between these factors are all important elements in deciding optimum controls designed to fit the operation to the individual rather than the other way round.

Techniques of risk reduction include: -

a)      Mechanical assistance;

b)      Improvements in the task;

c)      Reducing the risk of injury from the load;

d)      Improvements in the working environment; and

e)      Individual selection.

Manual handling is one of the most common cause of injury in the workplace, listed below are some important tips on avoiding injury, remember “if in doubt, don’t lift”.

Heavy items, or even lighter ones when held away from the body, may cause injury.  Such items should only be moved if it is necessary to do so. Large boxes of material should be broken down and moved in sections.  Wherever practicable, the load should be lightened.  If objects require regular movement, consider obtaining and using a mechanical aid such as a trolley.  Use the lift not the stairs; use a trolley not brute strength.

If something has to be moved and there is potential for harm, make use of the correct techniques to minimise the problem.  Injuries may be avoided by using the body carefully, taking care not to strain or cause undue pressure upon the spine or the stomach.

No specific weights, which people can safely lift, are laid down in general regulations, as much depends on specific circumstances and the capability of the person.

Guidelines give an example of 25 kilograms maximum (reduced by one third for females).

9.5       Hazards arising from the use of Manual Handling Aids

The alternatives and aids to manual handling include the use of a wide range of equipment including trolleys and conveyors, and some of these bring with them their own intrinsic risks.  Staff can run trolleys over their own or colleagues’ feet.  Conveyors carry goods that would otherwise require manual effort, but this can create trapping hazards if poorly designed and in some cases the goods themselves in movement may generate sufficient noise to cause damage to unprotected ears, as in bottling plants.

It is a principle in health and safety that when alternative methods are considered, in this case mechanical aids to manual handling tasks, a risk assessment be carried out on the proposed new methods rather than simple assuming that by tackling one problem others may not arise.

9.6       Risk Reduction


Wherever practicable manual handling tasks should be eliminated, for example: use the lift rather than carrying items up two flights of stairs.


Improve the tasks by applying the following principles:

·         improve workplace layout to improve efficiency

·         reduce the amount of twisting and stooping

·         avoid lifting from floor level or above shoulder height

·         reduce carrying distances

·         avoid repetitive handling


Reduce the load and improve its handling characteristics by applying the following principles:

·         make the load lighter or less bulky

·         make the load easier to grip

·         make the load more stable

·         make the load less damaging to hold

Individual Capacity

The following should be borne in mind when carrying out an individual risk assessment

·         strength, health and fitness of individual

·         pregnancy

·         level of training and information provided by employer

Mechanical Aids

All items of equipment should be suitable and fit for the purpose

9.6              Manual Handling and Health

Manual Handling is defined, for the purposes of the Manual Handling Operations Regulations 1992, as an activity involving the movement or support of a load by hand or by bodily force.  The Regulations do not cover bodily force exerted for any other purpose (e.g. pushing or pulling a lever to control a machine).

The definition is arbitrary, since hazards that accompany the application of a force will exist regardless of the object, which is being controlled.  This is not a loophole, since legislation stemming from other EC Directives will deal with handling issues related to design of machinery and workplaces.

The definition of manual handling is still very broad, and the range of injuries associated with it is potentially wide.  The risks to health from manual handling fall within 3 main categories.

i)                    Musculoskeletal injuries (i.e. those concerning the muscular or skeletal system of the body).

ii)                   Injuries caused by the load falling onto or trapping part of the handler or someone nearby.

iii)                 Injuries caused by the handler falling, perhaps against the load or other objects.

Musculoskeletal injuries may be either:

a)      acute, i.e. caused by an immediate failure of a bone, ligament or muscle, or

b)      chronic, i.e. caused by repeated actions carried out over weeks, months, or even years.

In general, acute injuries are associated with a few unusual exertions, such as lifting a heavy weight, while chronic injuries are linked to repetitious actions of lower force. In an individual case the distinction can be blurred.  Acute injuries may occur when an act triggers a failure in a part of the body that has suffered repeated but unnoticed damage over a long period.  Similarly, when an individual is fatigued then the risk of acute injury from relatively light forces increases. Sometimes the triggering act may seem insignificant, such as picking up a pen or bending to pat a dog.

9.8       Back Structure and its Implications

The back has an elaborate structure of bones, joints, ligaments and muscles and provides the support and strength for human body functions.  The structural stability of the body depends in particular upon the spine (comprising a number of bones, or vertebrae, one on top of another as illustrated in Figure 1 – upper) and the supporting given from sets of ligaments and muscles.  Between each pair of vertebrae there are separating discs of gel-filled fibrous material that enable the spine to bend and serve to cushion the effect of impacts.  The vertebrae also enclose the main nerve canal of the body, the spinal cord.

Figure 1 — Back structure and implications


9.9       Intervertebral Discs

Intervertebral discs are essential for the proper operation of the back.  When forces are applied to the back, the flow of gel within the discs ensures that the forces are distributed evenly onto the surfaces of the vertebrae.  The discs are designed to react primarily to compression, the force acting down the spine caused by the weight of the head and body.

The discs do not behave as if they are completely elastic and their recovery from deformation is slow.  If compression is maintained for a period longer than 15 minutes then a “creep” effect occurs and the disc will take longer to recover.

When forces are considerably greater than normal, for example when carrying or holding a heavy load, degenerative effects can also occur if there are repeated actions with relatively light loads.  Eventually, a lifting action may force the centre of the disc out through the containing fibres, putting pressure upon the nerves in the spinal column (see Figure 1 – lower).  This is termed a prolapsed disc (often mistakenly called a “slipped disc”) and is a painful and severe injury, with recovery taking many months.  A prolapsed disc often requires surgery.

Actions, which lead to relatively higher levels of damage to the disc, are twisting and stooping.  Twisting in particular causes stretching of the fibrous outer part of the disc, while stooping actions, i.e. bending the body from the waist make the pressure on the disc, as well as increasing considerably the total force transmitted down the spine.

Prolapsed discs form approximately 15% of back injuries and are less common than muscular or ligament strains.


·        avoid twisting where possible

·        avoid stooping where possible

·        intersperse manual handling tasks with other tasks if possible

·        allow sufficient rest and recovery periods

9.10     Ligaments

The ligaments are bundles of fibres, which hold the bones of the back together.  The fibres themselves are not usually elastic but are coiled up, and the ligaments stretch by straightening out the fibres.  If force is applied to ligaments when they are fully stretched, then they may rupture.  Continuous stretching may lengthen the fibres and loosen the arrangement of the vertebrae, making them prone to moving and trapping nerves.


·         avoid overreaching where possible

·         minimise frequency of stretching where possible

9.11     Muscles

Muscles play the dynamic role in the support and movement of the back.  Excessive forces acting upon these muscles, for example when trying to stop a falling load, can lead to tears in their fibres.  Unexpected forces can lead to injuries in unprepared muscles because there is a lack of resistance or to extra strains on discs or ligaments.

The muscles of the stomach also play an important role in lifting.  Tensing of the stomach muscles and holding the breath will increase the pressure within the abdomen, enabling the force being transmitted through the spine to be more evenly distributed.  This explains the common advice to take a deep breath and hold it before lifting.


·         minimise throwing and catching actions

·         train employees in safe lifting techniques

9.12     Fitness

The well-trained or fit individual will have a broad margin of safety between his/her maximal power or capacity on the one hand and what is being demanded of him/her physically on the other.  As work becomes physically less demanding then some physical activity should be included to provide the stimuli the body needs to function at best.  The less we do the less we are able to do and the vicious cycle progresses in a downward spiral.

There are four elements of fitness:

i)                    Cardiovascular or Oxygen Transporting System

If the job requires the heart to pump, for example, 10 litres of blood per minute at a rate of 120 beats per minute, it is a definite advantage if the heart is trained to pump 15 litres of blood per minute at a rate of 150 beats per minute.

ii)                  Strength

Muscles strength means that more of our muscle fibres (each muscle has between 100,000 and 1,000,000 fibres) are primed for work. It is achieved by high loading/low repetition exercises.

iii)                Muscle Endurance

This also depends upon the number of fibres primed to work but it is dependant upon the efficiency of the chemical turnover produced by muscle contraction.  Muscle fibres work in a relay system, i.e. when the energy of some fibres is spent others take over and so on repeating the cycle.  Endurance is achieved by low loading/high repetition exercise.

iv)                Flexibility

Flexibility would seem to be the Cinderella of fitness.  Little attention is paid to it but it is of equal importance as each of the other three elements.  In the usual physical training programme it is either forgotten altogether or such scant attention is paid to it that the effects are, at best, negligible.  Flexibility is of particular importance in achieving safe manual handling skills.

9.13     The Load

The “load” is the object, person or animal being handled, whether lifted, lowered, pushed, pulled or carried.  The features of the load, which are relevant to the handler, are related to:

a)      the force required to handled it

b)      its size

c)      how easy it is to grasp

d)      its stability

e)      external features that may create a hazard

9.13.1  Assessing the Load

9.13.2  Heaviness of the Load

As stated previously there is no single safe weight for lifting or single safe force for pushing or pulling.  Safe weights depend very much on the other features of the operation, such as the task, the environment and individual capability.

9.13.3  Shape and Size of the Load

The size and shape of the load are factors, which influence risks to the back in manual handling.  The further the centre of gravity of the load from the body, the greater the leverage effect on the spine, and the higher the risk of injury.  If a load has an even weight distribution, the centre of gravity is in the centre of the load.  The centre of gravity of a large load is therefore always further away from the body than the centre of gravity of a small load.  This is because the sheer physical bulk of a large load separates the handler from the centre of gravity of the load.  Even if two loads weigh exactly the same, the larger load will cause more strain due to the leverage effect.

9.13.4  Handling Points of the Load

Many loads are not particularly easy to grasp.  The load may be large, slippery or have sharp edges.  In these cases extra grip strength is needed, which fatigues the muscles more quickly.  As handlers tire, their grip will become weaker, and they may have to change either their grip or their posture to maintain control of the load.  The risk of dropping the load altogether is thereby increased.  Wherever possible a “power grip” should be applied to the load. A “pinch grip” is less forceful and there is a greater risk of fatigue.  Figure 2 shows the distinction between the two forms of grip.

9.13.5  Stability of the Load

If a load is unstable or its contents are likely to shift during handling (e.g. containers of fluids), the risk of injury increases since stresses on the spine are less predictable and the handler may not be prepared.

9.13.6  External Features of the Load

Assessing hazards arising from external features of a load is largely a matter of observation.  Factors to look out for are:

a)      sharp or rough edges which may increase the difficulty of holding a load and cause other hazards (splinters of wood, for example, create a risk of infection)

b)      hot or cold objects

c)      chemical hazards (these should be dealt with under the Control of Substances Hazardous to Health Regulations 2002)

d)      slippery loads, e.g. those which are wet, greasy or have a non-stick covering

e)      loads with damaged containers.

In all of these cases, protective gloves could be needed.  Gloves, however, may impair the grip and thereby increase the risk of dropping objects onto the feet.

Figure 2 — Power Grip versus Pinch Grip



 9.14     The Task

9.14.1  Distance of the Load from the Trunk

The distance of the load from the trunk is a crucial feature of manual handling operations, which involve lifting, lowering or carrying.  The further away a load is from the body, the greater the stress on the lower back.  The holder is also much more likely to topple over when the load is held away from the body.

If the holder can press the load into the body while lifting there is an additional frictional force, which reduces the spinal load and the fatiguing effect of the load on the arm muscles.  As a rule of thumb, the safe weight of a load that is held at arm’s length is approximately one-fifth of what it would be if the load were held close to the body.

9.14.2  Position of the Load in Relation to the Trunk

The position of the load in relation to the handler’s trunk influences the risk of back injury.  It is best if the load is situated directly in front of the handler, rather than to one side.  If the load is to one side, asymmetric weight distribution places extra stresses on the spine, a sideways bend is created, uneven pressure is put on the discs, and the centre of gravity is usually further away from the pivot point at the base of the spine, which increases the overall pressure on it.

9.14.3  Posture

Adopting a good posture during a manual handling operation minimises the risk of losing control of the load and enables the strain on different parts of the body to be better balanced.

Bad postural features are high priority risks, and measures should be taken to reduce them as soon as possible regardless of their exact nature.

9.14.4  Distribution of Weight on the Feet

The feet should be arranged so that the load can be evenly distributed.  One example of risky posture is having the body weight on the toes, especially if the handler is stretching upwards.  As a general principle, keeping the feet comfortably apart and, if possible, at right angles to each other, makes the greatest stability.

9.14.5  Twisting the Trunk

Twisting the trunk, which occurs frequently when picking up and moving off with items or when seated at a workbench, increases the stress on the lower back and reduces the safe load.  Wherever possible, therefore, the operation should be carried out without twist.  Guidance given suggests the following approximate relationship:

Degree of Twist

Reduction in Safe Load








9.14.6  Stooping

Stooping moves the centre of gravity of both the head and torso, and any objects, which are being held, away from the pivot point at the base of the spine.  The further away the centre of gravity from the pivot point, the greater the leverage effect upon the base of the spine and the greater the risk of injury.

The safe weight limit of the load when the handler is stooping is therefore much lower than it would be if the handler was upright.  This occurs whether the handler bends the back, or leans forward keeping the back straight.  An approximation for the reduction in safe load is provided by guidance as follows:

Angle of stoop

Reduction in Safe Load








Figure 3 illustrates both stooping and leaning postures.  The figure on the left is stooping, bending the hips and back, the figure on the right has bent the knees but is still leaning forward with a relatively straight back.  These two postures create high stresses on the back, and there is a high risk of injury regardless of the weight of load that is being carried.

Figure 3 —Stooping and leaning

9.14.7  Combined Risk Factors

When more than one risk factor has been identified, then the reduction in safe load may be much more than would be predicted by a simple additive process.  It is particularly important to identify if twisting is combined with stooping or stretching as shown for example in Figure 4.

Figure 4 — Combined risk

9.14.8  Seated Handling

The seated handler has to rely on the arms and torso for strength.  The much stronger leg muscles normally used for lifting play no role.  Moreover the ability to use the body as a counterbalance is severely reduced.  Consequently the safe limit for seated work is much lower than for standing work.  Guidance suggests that weights in excess of 5kg (3.5kg for women) should be regarded hazardous.  Posture features of the seated activity, i.e. stretching, stooping and twisting, reduce the safe limit further.  Lifting from below the level of the work surface will almost always create these risk factors.  Typical jobs with such elements are in factories where material is delivered to the side of seated operators, or checkout stations at stores.  Figure 5 shows an operator having to lean and twist to reach his work-pieces, precisely the circumstances, which create risks of back injury.  The acceptable safe weight limit for such actions would be effectively zero.



Figure 5 — Seated handling

9.14.9  Team Handling

If a load is too heavy or bulky for one person to manage, team lifting can be used.  A common example of this is team handling of patients in hospitals.  Safe loads for team handling cannot be calculated by simply adding together the safe load for each person in the team.

Under ideal conditions the:

·         Safe capacity of a 2-person team is two thirds of the sum of their individual capacities:

·         3-person team, the safe capacity is one half of their individual capacities.

Only you can judge how much you should move, if you are overweight, underweight or have other special medical problems be extra careful.

Think before you act, examine for awkward shapes or moving parts.  Plan your route.  Is there enough space to handle the object safely?  Ask for assistance if necessary.

9.15     Manual handling — Fundamental principles to be followed

i)                    Assess the load / environment – determine if its too heavy, unstable or naturally hazardous.  Will you have secure and even footing?  Is there a mechanical aid available, etc?

ii)                   Correct grip – an object is less likely to be dropped if it is held firmly in the palms of the hands rather than with the fingers. This ensures a more secure grip and allows the arms to be kept straight, transferring the weight of the load to the body.

iii)                 Arms close to body – a weight carried close to the body will enable the whole body to support the load. The body is capable of supporting tremendous weight without stress.

iv)                 Chin in – tucking in the chin will elongate the neck and prevent injury in that region. It also enables easier breathing and facilitates correct posture.

v)                  Straight back – the maintenance of a straight back is the most important principle of all. By keeping the back straight, pressure on internal organs is reduced and there is no pressure on the discs of the spine. Back muscles are then unlikely to be strained.

vi)                 Foot position – the body must be in balance when lifting or carrying, otherwise the lifter is likely to fall or cause undue strain trying to maintain balance. Putting one foot forward and to the side of the object gives better balance and control whilst lifting.

vii)               Use of legs – the leg muscles are the strongest in the body, and should be used as much as possible when lifting heavy objects, bending at the hips and knees whilst keeping the back straight allows these strong muscles to work well and safely.

Lifting, carrying and moving objects should be limited to the extent that you are confident of doing so without risk of personal injury — if in doubt, don’t lift.

9.16     End of module and next steps

Well done!  By reaching this point you will have finished studying this particular module.  You should now have sufficient knowledge to answer the questions contained at the end of the module.

Answers to the questions should be forwarded to your Health and Safety Manager.

Provided that you have answered the questions correctly, your Health and Safety Manager will forward to you your next self study module

To answer Module 9 Questions Click here