Prevention of musculoskeletal
disorders from performing
manual tasks in mining
workplaces
1
Overview of the workshop
• Aim and learning outcomes of the workshop
• Definitions
• Injuries from performing manual tasks – mechanism and
statistics
• Legislative responsibilities
• Anatomy and biomechanics
• The risk management process applied to manual tasks
• Who’s responsible
• Case studies
• Conclusion and questions
2
Aim of the workshop
To give participants the knowledge and
skills to identify hazardous manual tasks
and to assess and control risks arising from
those tasks.
This workshop will assist workplaces to fulfil their
legislative responsibility to protect employees
from hazardous manual tasks.
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Learning outcomes
• Provide the definition of a manual task, a hazardous manual task and
a musculoskeletal disorder
• Explain the legislative requirement to manage the risk resulting from
hazardous manual tasks
• Explain how performing manual tasks can lead to injury
• Have an understanding of anatomy and biomechanical principles
• Participate effectively in the risk management process applied to
manual tasks including:
– Recognising hazardous manual tasks
– Assessing the risk of injury, the source of the risk and the severity of the
risk
– Developing risk controls to effectively reduce the risk by altering the
source of the risk identified in the risk assessment process.
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Definitions
Manual task is a label given to any activity that requires a
person to use their physical body (musculoskeletal system)
to perform work.
This includes work that involves the use of force for:
 Lifting/lowering; pushing/pulling; carrying; moving; holding;
or restraining anything
and work that involves:
 Repetitive actions; sustained postures; and concurrent
exposure to vibration
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Examples of manual tasks
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Definitions continued
Hazardous manual tasks refer to any manual tasks that involve
certain characteristics that increase the risk of injury, including:




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
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Repetitive or sustained application of force
Repetitive or sustained awkward postures
Repetitive or sustained movements
Application of high force
Exposure to sustained vibration
Involve handling of person or animal
Involve handling of unstable or unbalanced loads that are
difficult to grasp or hold
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Definitions continued
Hazardous manual tasks can lead to a variety of injuries and
conditions collectively referred to as musculoskeletal
disorders (MSD) including:
 Sprains and strains of muscles, ligaments and tendons
 Back injuries, including damage to the muscles, tendons,
ligaments, spinal discs, nerves, joints and bones
 Joint injuries or degeneration, including injuries to the
shoulder, elbow, wrist, hip, knee, ankle, hands and feet
 Bone injuries
 Nerve injuries
 Muscular and vascular disorders as a result of hand-arm
vibration
 Soft tissue hernias
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Injuries from performing manual tasks
Injuries occur when forces on structures of the
musculoskeletal system (e.g. muscle, ligaments, tendon,
bone) are greater than the structures can withstand
• Acute injuries – sudden damage to musculoskeletal
system, occurs as consequence of single exposure to
high force
• Cumulative injuries – cumulative wear and tear on
musculoskeletal system, caused by repeated or
prolonged exposure to lower levels of force
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Extent and cost of injuries in WA mining
 Injuries from performing manual tasks consistently
account for about 1/3 of all new LTIs and DIs and over
50% of all injury recurrences
 About 2/3 of these LTIs and DIs and 90% of these
recurrences are serious (14 or more days/shifts lost)
 These injuries account for nearly 40% of all LTI
compensation costs and approximately 45% of the total
days lost from workplace injuries.
LTI Lost time injury, requiring absence from work for a full shift
DI Disabling injury, unable to work usual job any time of shift/alternate duties
Sources: AXTAT data 2004-2007 and WorkerCover data 2005-2007
Source: Workers' Compensation
Statistical Report 1998/9 - 2001/02
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Overview of legislation
• Resources Safety administers the Mines Safety
and Inspection Act 1994 (MSI Act) and the Mines
Safety and Inspection Regulations 1995 (MSI
Regulations)
• The MSI Act sets out broad duties with respect to
OSH, supported by MSI Regulations
• Codes of practice and guidelines provide practical
guidance
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Duties – Employers*
Employers have a general duty to provide and
maintain a working environment to protect the
health and safety of their workforce including a
requirement to:
– Provide and maintain workplaces, plant and systems of
work
– Provide information, instructions, training and
supervision
– Consult and cooperate with safety and health
representatives and employees
so that employees are not exposed to hazards.
*Employer is anyone who employs a person in a mining operation.
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Duties – Employees*
Employees are obliged to take reasonable
care to ensure their own and others’ safety
and health including a requirement to:
– Cooperate with employers
– Follow instructions
– Report hazards
*Employees include contract and labour hire personnel
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Legislative requirement
• If a hazardous manual task is identified, all duty
holders must fulfil their obligations to reduce the
risk of injury to workers completing the task
• Risk management process is recommended to
fulfil obligations
– hazard identification
– risk assessment
– risk control
– control evaluation
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Overview of anatomy and biomechanics
•
•
•
•
Anatomy of the spine
Body positions and postures
Types of muscle work
Principles of biomechanics
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Anatomy of the spine
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Trunk (back) positions
Flexion and extension
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Trunk (back) positions
Side flexion and rotation
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Wrist positions
Extension, neutral and flexion
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Hand and forearm positions
Pronation and supination
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Neutral postures
• Head and neck – level or bent
slightly forward, forward
facing, balanced and in-line
with the trunk
• Hands wrists and forearms –
all straight and in-line
• Elbows – close to the body
and bent 90o to 120o
• Shoulders – relaxed and
upper arms hang normally at
the side of the body
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Neutral postures
continued
• Thighs and hips – parallel to
the floor when sitting;
perpendicular to the floor
when standing
• Knees – same height as hips
with feet slightly apart when
sitting; aligned with hips and
ankles when standing
• Back – vertical or leaning
slightly back with lumbar
support when sitting; vertical
with an S-shaped curve when
standing
Source: NIOSH IC 9509: Ergonomics Processes Implementation Guide and Tools for the Mining Industry
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Types of muscle work
• Dynamic
Muscle contraction and movement
• Static
Muscle contraction and no movement
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Principles of biomechanics
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Using the spine as a crane
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Risk management process
Source: National Code of Practice for the Prevention of Musculoskeletal Disorders
from Performing Manual Tasks at Work
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Overview of hazard identification
Hazard identification is a way of analysing tasks
to find out which tasks cause or contribute to
musculoskeletal disorders. That is, a process to
identify hazardous manual tasks.

Check sources of information such as injury and
hazard reports

Consult with workers, supervisors and safety and
health representatives

Look at task and identify any of the characteristics that
make it hazardous
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Reporting hazardous manual tasks
• All personnel at mining
workplaces have a
statutory obligation to
report hazards
• Being proactive by early
reporting of concerns
such as discomfort, pain,
when completing a
manual task may
prevent serious injury
Source: NIOSH IC 9497: Ergonomics and Risk Factor
Awareness Training for Miners
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Example of hazard identification form
Source: Burgess-Limerick, R (2009) Procedure for Managing Injury Risks Associated with Manual Tasks
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Example of discomfort survey form
Source: National Code of Practice for the Prevention of Musculoskeletal Disorders
from Performing Manual Tasks at Work
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Potentially hazardous manual tasks
Research suggests a manual task should be considered
potentially hazardous if any of the following apply:
• An injury (musculoskeletal disorder) has been recorded
that was associated with performance of the task
• Any employee is physically incapable of performing the
task, or the task can only be done for a short time
• Any employee reports discomfort associated with the
manual task
• Employees have improvised controls for the task
Burgess-Limerick (2008) Procedure for Managing Injury Risks Associated with Manual Tasks
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Potentially hazardous manual tasks
continued
• Employees doing this task have a higher turnover,
or rate of sick leave, than elsewhere in the
organisation
• The mass of any object, person, or animal being
handled exceeds 16 kg
• If the force exerted on any object, person or animal
exceeds 200 N
• If the postures adopted to perform the task involve
substantial deviations from neutral
Burgess-Limerick (2008) Procedure for Managing Injury Risks Associated with Manual Tasks
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Potentially hazardous manual tasks
continued
• If the task involves static postures held for longer than 30
secs and the task is performed for more that 30 mins without
a break, or for more than 2 hrs per shift
• If the task involves repetitive movements of any body part
and is performed for more than 30 mins without a break, or
for more than 2 hrs per shift
• If the task is performed for longer than 60 mins at a time
without a break
• If the task is performed for longer than 4 hrs per shift
• If exposure to whole body vibration (vehicles) or peripheral
vibration (power tools) exceeds 2 hrs per shift
Burgess-Limerick (2008) Procedure for Managing Injury Risks Associated with Manual Tasks
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Overview of risk assessment
Risk assessment is about understanding the
problem. The risk assessment determines:
• whether the task poses or increases risk of injury
(musculoskeletal disorder)
• source/s (underlying/root cause/s) of the risk
• the severity (level) of risk
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Risk factors
• Direct risk factors: Risk factors that are known to lead to
musculoskeletal disorders are:
– Postures and movements of worker
– Forces (exertion) involved in task
– Duration and frequency of task
• Indirect risk factors: Risk factors that are known to contribute to
the risk of musculoskeletal disorders are:
– Work environment
– Systems of work, work organisation and work practices
– Exposure to vibration
• The risk of developing a musculoskeletal disorder significantly
increases where there is more than one risk factor present in the
task
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Risk factors: postures and movements
If a task involves postures and movements that are:
• repetitive (more than twice a minute) or
• sustained (more than 30 seconds at a time) and/or
• awkward (away from the neutral position)
then the risk of injury (musculoskeletal disorder) increases
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Examples of postures and movements that
increase the risk of injury
• Working with the trunk or neck twisted or
bent
• Working with hands above shoulder height
• Reaching forward or sideways
• Reaching or twisting behind the body
• Working in kneeling, squatting, crawling or
lying
• Working with extreme wrist bending or
twisting
• Working with tight pinch grips
• Carrying or exerting force with one hand or
on one the side of the body
• Working in a static (held) position
• Exerting force while in an awkward posture
• Repetitive lifting, lowering, carrying,
pushing, pulling, restraining, holding
Photograph Source: NIOSH IC 9497: Ergonomics and Risk Factor Awareness Training for Miners
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Risk factors: force
• A manual task that involves high force is
one that people in the working population
would find difficult because of the effort it
requires
• Where there are high forces involved in
the task, even if they are not repetitive or
sustained, there can be a risk of injury.
• The risk in tasks involving high force is
related to:
– the intensity of the force
– the speed of the force
– whether the force is jerky or sudden
Photograph Source: NIOSH IC 9497: Ergonomics and Risk Factor Awareness Training for Miners
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Risk factors: duration and frequency
• Tasks that continue over a long
period or are repeated over the
work day, increase the worker’s
exposure
• Risk of injury is influenced by:
– how long the task is carried out
(duration); and
– how often the task is done
(frequency)
Photograph Source: NIOSH IC 9497: Ergonomics and Risk Factor Awareness Training for Miners
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Risk factors: work environment
Aspects of the work environment that can contribute to
the risk of injury when performing manual tasks include:
Thermal environment – cold, heat, humidity and wind
Workplace lighting – low levels of light, glare
Floor surfaces – slippery, uneven, variation in levels
Housekeeping – obstructions, trip hazards
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Risk factors: work systems,
organisation and practices
Aspects of the work organisation, work practices and
systems of work that may increase the risk of injury
include:
– pace of work and time constraints
– abilityof workers to influence workload or work
methods
– level of resources and guidance available
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Risk factors: vibration
•
The longer a worker undertaking manual tasks is
exposed to vibration, the greater the risk of a
musculoskeletal disorder
•
Workers may be exposed to two types of vibration:
– Whole-body vibration
– Hand-arm vibration
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Source of risk
Determining the source (i.e. underlying cause) of the risk/s in a
hazardous manual task is an important part of the risk assessment
Sources of risk include:
– Work area design and layout
– Nature of load being handled
– Nature of the items (including hand tools, plant and equipment)
– Working environment (including thermal environment, floor or
ground surfaces, obstructions, lighting, noise and vibration)
– Systems of work, work organisation, work practices
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Severity of risk
Determining the severity of the risk helps to prioritise
hazardous manual tasks for action
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Example of risk assessment checklist
Copyright 2007-2008 Burgess-Limerick & Associates www.burgess-limerick.com
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Overview of risk control
• Risk control means implementing effective measures to
eliminate or minimise risk of injury (musculoskeletal
disorders).
• Risk control process determines what needs to be done to
alter the sources (underlying causes) of risk identified by
the risk assessment, in order to eliminate or minimise the
risk of injury.
• Control measures should follow the hierarchy of controls.
Elimination or redesign/engineering controls should be
implemented over administrative and PPE controls
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Approach to risk control
Eliminate the hazardous manual task
or
Redesign the work, workplace or equipment to
minimise the risk of injury (musculoskeletal
disorders)
and
Provide appropriate manual task training
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Risk control: elimination
• The ultimate control measure is to eliminate the
hazardous manual task
• Best practice includes:
– Eliminating potential hazardous manual tasks
during the design of workplaces, equipment,
tools, plant and systems of work
– Incorporating ergonomics specifications into
purchasing procedures
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Risk control measures
Alter the source (underlying cause) of the risk by altering:
• design and layout of the workplace
• nature of the load (including using mechanical aids or
assistive devices)
• nature of the items used during manual tasks (including
hand tools)
• working environment
• work organisation and work practices, including systems
of work
to minimise the risk of injury (musculoskeletal disorder) as far
as is practicable
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Alter workplace design and layout
Location and design of switch changed to reduce reach and
allow the operator’s arm to be in a neutral posture
Source: NIOSH IC: 9491 Ergonomics and Mining: Charting a Path to a Safer Workplace
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Alter workplace design and layout
Access to wash-plant area changed to reduce awkward postures
Source: ACARP Project C11058: Reducing Musculoskeletal Risk in Open Cut Coal Mining
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Alter workplace design and layout
Putting the weighing scale on an elevated cart and locating it next to the
conveyor eliminates the need to carry items to the scales and reduces
stooping (bending back or trunk) when lifting items on and off the scale
Source: NIOSHTIC-2 No. 2003465: Ergonomics Interventions at Badger Mining Corporation
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Alter nature of the load
Attaching a simple handle to this wheel chock improves working posture
Source: NIOSH IC 9507 Reducing Low Back Pain and Disability in Mining
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Alter nature of the load
Using mechanical aids or assistive devices reduces manual
lifting, lowering, carrying, pushing, pulling and holding
Source: NIOSH IC 9507 Reducing Low Back Pain and Disability in Mining
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Alter nature of the items
Suspend heavy tools. The weight of impact wrench is being supported by a
strap hung from an overhead crane
Source: NIOSH IC: 9491Ergonomics and Mining: Charting a Path to a Safer Workplace
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Alter nature of the items
Use power hand-tools instead of manual hand-tools. Using cable cutters
attached to a power drill eliminates repetitive, forceful exertions required to
operate manual cable cutters
Source: NIOSHTIC-2 No. 2003465: Ergonomics Interventions at Badger Mining Corporation 56
Alter work environment
Alter the work environment to reduce the risk of injury
(musculoskeletal disorder) by altering the:
• thermal environment – reducing and managing exposure
to cold, hot, humid and windy conditions
• floor surfaces and housekeeping – selecting and
maintaining appropriate floor surfaces, steps and ramps and
keeping work areas clean, tidy and free of clutter and
obstacles
• lighting – selecting lighting to suit the task being performed
• vibration – controlling exposure to vibration, at the source;
and/or the path of the vibration; and/or the vibration
received by the worker
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Alter the work
Alter work organisation and work practices, including
systems of work, to reduce the risk of injury
(musculoskeletal disorder) by:
– implementing task rotation
– implementing work breaks
– altering work rates
– changing work methods
– reducing shift duration
– avoiding peak workloads
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Training
General training for manual tasks risk management
• During induction
• As part of risk control programme
Task-specific training
• During induction to the task
• Refresher training
• When tasks and/or equipment are changed
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Example of risk control documentation
Source: McPhee, B (1993) Ergonomics for the Control of Sprains and Strains in Mining.
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Monitor and review
• Monitoring and reviewing the implemented control
measures is essential to ensure their effectiveness and
that no new hazards have been introduced
• The process should include:
– consulting with workers
– observing the tasks
– monitoring any hazard / incident / injury reports
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Who’s responsible?
• Who should be involved?
• What consultation is needed?
• Should records be kept?
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Case studies
• Work in small groups (2-4 people per group)
• If possible get into a group with people with the
same job or occupation
• Discuss the case study and complete the risk
assessment and risk control sections
• Report on the major risk factors found in the risk
assessment, and the control measures
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The aim is to reduce the risk of injury
(musculoskeletal disorders) from performing
manual tasks at work, using the risk management
process of:
– identifying hazards
– assessing risks
– controlling risks
– monitoring and review
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References and further information
• Resources Safety’s guidance document
Implementing an Effective Program to Manage
the Risks Associated with Manual Tasks provides
a list of references and resources for further
information
• Visit the Hazardous Manual Tasks page at
www.dmp.wa.gov.au/7221.aspx
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