Office Ergonomics

Course Objectives1) To be able to recognize ergonomic hazards in the

office;2) To be able to utilize efficiencies of various office

equipment, tools and accessories to the fullest and reducing ergonomic risks;

3) To be able to suggest appropriate control measures aimed in mitigating office ergonomic hazards;

4) To be able to learn basic principles of manual handling;

5) To be able to lift objects in the office in a safe manner

Agenda for Today• Office Equipment, Tools and Accessories• Office Ergonomic Risk Assessment & Checklist• Group Exercises, Presentations, Videos• Tea Break• Manual Materials Handling• Safe Lifting Demonstrations• Manual Handling and Safe Lifting Videos• Assignment

Office Ergonomics

Topics• Definitions• An ‘ergonomic chair’• Desks: adjustable and non-adjustable• Monitor• Laptops• Keyboard• Computer mouse• Other office accessories• Lighting and Glare• Arranging your office• Risk Assessment• Office Ergonomics Video (UCLA)• Group exercises

DefinitionsErgonomics: ‘nomoi,’ natural laws; ‘ergon,’ work

: science of fitting workplace conditions and jobdemands to capabilities of the working population (Ministry ofManpower)

Musculoskeletal disorders: illnesses and injuries that affectone or more parts of the musculoskeletal system

Manual handling: Transporting or supporting of a load byone or more members of staff, which includes lifting, puttingdown, pushing, pulling, carrying or moving, and by reason ofits characteristics of unfavourable ergonomic conditions,involves risk. (Northern Ireland Practice and Education Council for Nursing andMidwifery, 2009)

Reference

Office Ergonomic Risks• Awkward postures• Prolonged or uninterrupted work• Repetitive work• Poor workstation design• Visual discomfort of video display terminals: lack of

contrast and sharpness in display, undue amount of flicker, prolonged close vision work

• Poor office environmental conditions: poor lighting and glare

• Work stress

Courtesy of Burt Chiropractic, 2012

Courtesy of BodyBilt Ergonomics

Courtesy of Environmental Handling Systems Ltd., 2009

SS 514, 2005

Components of an Office Chair• 5 caster swivel base• Armrests• Height adjustable seat pan• Tilt adjustable back rest• Seat pan wide and deep enough to fit user comfortably,

adjustable in angle• Padding for low back area that is curved to fit the shape

of the back• Height adjustable back rest• Backrest wide enough to fit the back comfortably

The Chair

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

The Chair

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

The Chair

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Adjustable Desk

Courtesy of progressive.com.au

Non-adjustable Desks• If the work surface is too low, raise the desks using a

stable support (i.e., blocks under desk legs) until work surface or keyboard is at elbow height.

Courtesy of Squidoo, LLC

The Monitor: Good Practices• Screen located approximately an arm’s length away from the

user

• Screen is located directly in front of the user, and can be raised if required

• Top of screen is approximately at eye level. Centre of screen is at shoulder height.

• Glare and reflection on screen are eliminated.

• 20 feet away for 20 seconds every 20 minutes to rest the eyes

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Good or Bad Practice?

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Laptop Computers

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Laptop Computers: Good Practices• Get a large screen• Place the screen at eye level• Don’t slouch• Use a separate keyboard (for extended periods)• Use a separate mouse• Recline slightly• Knees should be at about the level of your hips• Make your chair work for you• Take a break• Travel light

Laptop Computers: Good Practices• Use a computer docking station.• Continue to use laptop screen and connect an

external full-sized keyboard

Courtesy of Camera Phones Plaza, 2010

Computer Keyboard: Good Practices• Put keyboard slightly below elbow level and close to

body. • Keyboard should be angled in a way that wrist

remains straight

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Computer Mouse: Good Practices• Release mouse at frequent intervals to reduce pressure on

wrist and forearm muscles

• Place mouse on mouse mat. Use whole arm when utilizingmouse

• Ensure wrists in neutral position. Elbow positioned close tobody when utilizing mouse

• Mouse pad should be placed as close as possible to thekeyboard

• Keyboard and mouse should be positioned at the same level

Slimline, Low Profile Mouse

Courtesy of PCMag.com; Future US Inc., 2012

SS 514, 2005

Office Ergonomic Accessories: Footrest• Recommended when keyboard users are unable to

firmly position their feet on the ground

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Office Ergonomic Accessories: Document Holder• Useful for assisting the neck to remain in neutral position• Should be the same distance from the eyes as the

monitor and at the same height as the monitor

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Office Ergonomic Accessories: Wrist Rest• Reduce contact pressure on wrists from sharp

workstation edges• Heel of hand should only be resting on wrist pad

when taking a break• Be high enough to keep wrist in straight, neutral

position• Be made of moderately firm and comfortable material

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Office Ergonomic Accessories: Headset• Important for ensuring neck remains in neutral

position when phone is used for frequent/extendedperiods of time

• Prevents unnecessary muscle activity of arms andshoulders

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Office Ergonomic Accessories: Screen Filters• Reduces visual discomfort caused by reflections

and glare on screen

Courtesy of Euroffice Ltd.

Proper Working Posture at the Computer• Feet supported on the floor, or with a footrest• Thighs supported by chair seat with no pressure caused

by front edge of the seat under the thighs• Upper body upright with lower back firmly supported by

the backrest• Shoulders in relaxed position, not hunched• Elbows and upper arms close to the body• Forearms parallel to the ground, wrists in a neutral

position (straight) when utilizing keyboard & mouse• Neck remains in neutral position (i.e., not looking

upwards or downwards) when viewing the monitor

Office Lighting: Glare• Direct glare: light shines directly in the eyes• Indirect glare: light is reflected from a surface

Courtesy of University of Guelph

Reducing Glare• Position monitor perpendicular to windows and

between overhead light panels• Use curtains and blinds to control amount of natural

light• Eliminate light sources that shine directly into the

eyes• Eliminate light sources that reflect directly into the

eyes• Use of LCD (flat panel) monitors• Dim overhead lights• Angle monitor away from the light• Place filters, fixtures on overhead lights• Tint windows

Stretches for Wrists and Arms

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Stretches for the Neck

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Upper Body Stretches

Courtesy of Occupational Health Clinic for Ontario Workers Inc.

Arranging your Office• Files and books that are used most often should be kept

within reach.• Frequently used files are in the middle drawer or closest

to elbow level• Locking system for filing cabinets so that no more than

one drawer can be opened at once• File and desk drawers should be kept closed when not

in use to avoid trips, bumps and scrapes• Heavy books should be placed on the middle shelf or

around elbow level

Desk Arrangement

• Items on desk should be arranged based on their weight, frequency of use• Frequently used items should be located close to the user at a minimal

reach distance.

SS514, 2005

Office Ergonomic Risk Assessment

What is Risk Management?

• New safety and health management frameworkunderpinned by the new Workplace Safety andHealth Act (WSH Act).

• Entails:– Risk assessment of any work activity;

– Control and monitoring of such risks; and

– Communicating these risks to all personsinvolved.

What is Risk Assessment?• An integral part of risk management

• It is the process of1. Identifying safety and health hazards associated with

work, (Hazard Identification)2. Assessing the level of risks involved, (Risk Evaluation)3. Prioritizing measures to control the hazards and reduce

the risks (Risk Control)

A guide to WSH (Risk Mgt) Reg by MOM

Hazard Identification

Risk Evaluation

Risk Control

Hazard and RiskHAZARD“anything with the potential to cause bodily injury,and includes any physical, chemical, biological,mechanical, electrical or ergonomic hazard”(Workplace Safety & Health (Risk Management) Regulations)

RISK“likelihood that a hazard will cause a specific bodily injury to any person” (Workplace Safety & Health (Risk Management) Regulations)

Measured in terms of: Severity and Likelihood

Why Risk Assessment?

• Comply with Workplace Safety & Health (Risk Management) Regulations;

• Prevent incidents and injuries;

• To assess if a work process is safe to proceed; and

• To assess the adequacy of the existing control measures

• Protect ourselves from injuries

Name of Department Location of Lab

Name of Laboratory Name of PI

Name of Researcher/LO Name of Activity/Experiment

No Description/Details of Steps in Activity

Hazards Possible Accident / Ill Health & Persons-at-Risk

Existing Risk Control (Mitigation) Severity Likelihood (Probability)

Risk Level Additional Risk Control Person Responsible By (Date)

1

2 03 04 05 06 07 08 09 0

10 0

Conducted By Approved ByName

Signature

Approval date Next Revision date(Maximum 3 years)

1. Hazard Identification 3. Risk Control

Activity-Based Risk Assessment Form

Rating Severity Severitymeaning

Examples

1 Low No injury, injuryor ill-health requiring first aid treatment only

Minor cuts & bruises, irritation, ill health with temporary discomfort

2 Medium Injury requiringmedical treatment or ill health leading to disability

Lacerations, burns, sprains, minor fractures, dermatitis, deafness, work-related musculoskeletal disorders

3 High Fatal, serious injury, or life-threatening occupational disease

Amputations, major fractures, multiple injuries, occupational cancer, acute poisoning and fatal diseases

Risk Assessment Spreadsheet vs. Checklist• Risk assessment spreadsheet allows to recognize

hazards from office activities, possible persons-at-risk, severity and likelihood of hazards, and controls to mitigate such

• Office ergonomics checklist were generated from the risk controls. Follows hierarchy of risk controls

Common MSDs among office workers

Disorder Description Office TasksCarpal tunnel syndrome Compression of median

nerve of wristTyping, keying

Cubital tunnel syndrome Compression of ulnar nerve below elbow notch

Resting forearm near elbow on hard surface

Neck tension syndrome Irritation of trapeziusmuscle of neck

Typing, keying

Shoulder tendinitis Shoulder disorder of rotator cuff

Packing, storing,reaching, lifting

Thoracic outlet syndrome

Compression of nervesand blood vessels of clavicle

Typing, keying, stacking, material handling, carrying heavy loads with extended arms

Anna (ed.), 2011

Musculoskeletal Disorder Symptoms (MSDs)• Neck shoulder complaints• Visual Discomfort: tired, dry or irritated eyes,

blurred vision• Muscle fatigue • Stiffness • Numbness • Tingling • Burning sensations • Heaviness • Weakness or clumsiness in the hands (dropping

things)

Office Scenarios, Risk Factors and Potential MSDs Scenario Risk Factor Potential MSDsTyping with bent wrists Awkward posture Tendinitis of hand & wrist,

carpal tunnel syndromeElevated forearms & bent elbows while typing

Static loading, awkward posture

Reduction of blood circulation. Stress on tendons in the joint

Hard wrist rests, fabrics with rough material build, sharp edges on keyboard trays

Contact stress Carpal tunnel syndrome. Numbness, tingling, burning sensations in fingers

Hunching shoulderswhile typing

Awkward posture Neck muscle tension

Washington State Dept. of Labor & Industries, 2002

Office Scenarios, Risk Factors and Potential MSDs Scenario Risk Factor Potential MSDsLong reaches to input devices (e.g., mouse/trackball/touch pad)

Awkward posture Fatigue in shoulder and neck muscles. Numbness, tingling & burning sensations in fingers

Elevating hand or reaching down to input devices

Static loading, awkward posture

Reduction of blood circulation. Stress on arm and hand joint. Numbness, tingling & burning sensations in fingers

Gripping the mouse tightly Force Tendon strain on hand and wrist. Numbness, tingling & burning sensations in fingers

Washington State Dept. of Labor & Industries, 2002

Office Scenarios, Risk Factors and Potential MSDsScenario Risk Factor Potential MSDsLooking up or down the monitor

Awkward posture Neck muscle fatigue

Twisting the head while looking at the monitor

Awkward posture Neck muscle loading

Leaning forward to read blurry text on screen

Awkward posture Headache, muscle strain

Sitting too far from monitor Awkward posture Neck, lower and upper back discomfort

Tilting head to one side to hold telephone handset between ear and shoulder

Awkward posture Neck muscle and uppershoulder strain, muscle overstretch

Reading documents laid flat on desk surface

Awkward posture:leaning forward, tilting head downward

Neck, upper back, low back discomfort

Washington State Dept. of Labor & Industries, 2002

Office Scenarios, Risk Factors, and Potential MSDsScenario Risk Factor Potential MSDsLack of low back support Awkward posture Back stress, low back painFeet not touching floor Contact stress Reduced blood circulation.

Leg and foot tingling, numbness

Lack of space between edge of seat and back of knees

Contact stress Reduced blood circulation to legs and feet. Leg and foot tingling, numbness

Armrests too high Awkward posture: hunching shoulders

Muscle tension, fatigue

Armrests too low Awkward posture: leaning to one side

Uneven posture, muscle imbalance

Hard armrests Contact stress Elbow pressure. Numbness, tingling & burning sensations in fingers

Washington State Dept. of Labor & Industries, 2002

Office Scenarios, Risk Factors, and Potential MSDsScenario Risk Factor Potential MSDsHands/wrists contact desktop edge

Contact stress Carpal tunnel syndrome. Numbness, tingling & burning sensations in fingers

Extended arm reaching to secure desktop accessories

Repetition and awkward postures

Fatigue

Inadequate space for knees and legs under work surface

Contact stress, static loading

Bruising if bump frequently to underside of desktop. Impact trauma to knees and thighs

Long reaches to items stored overhead

Awkward posture Muscle overstretching, increased strain

Washington State Dept. of Labor & Industries, 2002

Office Ergonomics Videohttp://www.youtube.com/watch?v=IAMKVJnHNsA

Exercise

Exercise

Group ActivityPopulate your 3 x 3 risk assessment spreadsheet with the

following activities in offices:• Using a puncher for filing documents• Filing of documents• Stapler use• Working with video display terminals• File retrieval from shelves• Use of photocopierIdentify ergonomic hazards arising from these activities,possible musculoskeletal disorders that may arise, andrisk controls that may mitigate these hazards.

Office Safety Videohttps://ivle.nus.edu.sg/bank/media/viewmedia.aspx?Ch

annelID=ad25a54e-107d-4a99-a777-f6b4e0d34908&MediaItemID=07eb4a54-d985-4c2e-b27b-3b0e2672846e&Player=WMP&Referrer=EC&eu=oshbaa

Tea Break!

Manual Materials Handling

Topics• Why manual handling?• Risky Moves• Body physics: core muscles, biomechanics• Risk Factors• Risk Controls• Proper Lifting Techniques• Manual Handling, Principles of Safe Lifting videos

Why Manual Handling?• Heavy lifting isn’t typically a requirement of most

office jobs; however, some lifting is inevitable• The way materials are stored and moved around the

office can cause risk factors for injury• Common musculoskeletal disorders from improper

lifting and carrying include injuries to the lowerback, upper back and shoulders

• Injuries from improper lifting and carrying havealways been part of office work

• Lifting injuries comprise 1/3 of all the injury claims inthe office each year (Washington State Dept. of Labor & Industries, 2002)

Risky MovesCertain actions are more likely to cause backinjuries than others. Anytime you find yourselfdoing one of these things, you should think:DANGER! My back is at risk!

Heavy lifting...especially repetitivelifting over a long period of time

Twisting at the waist while lifting orholding a heavy load.

Reaching and lifting...over your head oracross a table.

More Risky MovesLifting or carrying objects with awkward or odd shapes

Working in awkward, uncomfortablepositions...gardening, kneeling, tasks that require you to bend over for long periods of time...

Also, sitting or standing for too longwithout shifting.

Core Strength Muscles

Courtesy of Pilates Workers of New York Inc.

Back Biomechanics: Standing up Straight

71

23 kg

5 cm

force on spine

4.5 kg

45 kg

25 cm

Adding up load:Load in hands 4.5 kg.Torso weight 45.0 kg.Muscle force 23.0 kg.Total load 72.5 kg.

Lifting Guide:Goal ≤ 347 kilograms

Back Biomechanics: Stooping Forward

72

Adding up load:Load in hands 4.5 kgTorso weight 45.0 kgMuscle force 270 kgTotal load 319.5 kg

270 kg

5 cm

force on spine

25 cm

4.5 kg

45 kg

50 cm

Torso and arm weight

Resultant muscle force

Load in the hands

Lifting Guide:Goal ≤ 347 kilograms

Primary Risk Factors Risk of low back pain injury when lifting/carrying objects depends on 5 main factors:

- Weight of object- Distance of object from body- Body position while carrying/lifting object- Frequency of lift- Twisting while carrying load

74

Biomechanics of the Shoulder

Preferred posture:Strongest and most stable

Raising the elbow to shoulder height or higher:• Significantly reduces shoulder strength • Increases the risk of injury

Arms close to the sides Arms extended away from the body

Gutmann, 2005

The Forces InvolvedAnytime you bend or lean over to pick something up withoutbending your knees, you put tremendous pressure on yourlower back.

If your waist is not centered, lifting a 4.5 kg object actually puts45 kg of pressure on your lower back.

Gutmann, 2005

The further you bend, and the more you extend your arms, the more significant

the risk of injury!

Gutmann, 2005

Contributing Factors to Handling/Lifting InjuriesPoor Physical Condition…

Stomach muscles provide a lot of the supportneeded by your back.Weak, flabby stomach muscles may preventthe back from getting the support it needs,especially when lifting or carrying heavyobjects.

Poor postureIt is best to try to maintain the back in its natural "S" shapedcurve. You want to avoid leaning forward (unsupported)when you sit, or hunching over while you're standing.

Contributing Factors to Handling/Lifting Injuries

Gutmann, 2005

Contributing Factors to Handling/Lifting Injuries

Extra weight…The more you weigh, the morestress it puts on your backevery time you bend over--on a10:1 ratio.

Risk Factors to Handling/Lifting Injuries

Stress…Tense muscles are more susceptible to strains and spasms.

Risk Factors to Handling/Lifting InjuriesOverdoing it…Don’t be afraid to say, “This is too heavy forme to lift alone. Will you help me?”

Courtesy of about.com, 2012

Scenarios, Risk Factors & Potential MSDsScenario Risk Factor Potential MSDsLifting items located between knee and shoulder height

Awkward posture:bending, stooping, kneeling, reaching

Discomfort on lower back, upper back and shoulder, knees

Lifting away from the body Force, awkward posture: reaching, bending

Discomfort on lower back, upper back and shoulder, knees

Lifting from the floor Awkward posture:bending, stooping, kneeling, reaching

Discomfort on lower back, upper back and shoulder, knees

Carrying loads at longdistances

Sustained exertions Muscle fatigue, strain

Lifting-assistive devices are not readily available

Force Discomfort on lower back, upper back and shoulder, knees

Washington State Dept. of Labor & Industries, 2002

Scenarios, Risk Factors and Potential MSDsScenario Risk Factor Potential MSDsJob with lifting as the only task

Repetition Fatigue, increased risk of injury

Washington State Dept. of Labor & Industries, 2002

Preventing Lifting Injuries: Risk Controls

Basic Guidelines• Plan the lift (3-2-1 LIFT!)• Object closed and centered to the body• Diagonal footing when lifting an object off

the floor• Use ‘core strength’ muscles: upper, middle

and lower abdominal muscles• Bend the knees, lift with the legs• Look ahead• Don’t do it alone

Preventing Lifting Injuries: Risk Controls Avoid Lifting and Bending Whenever You Can!

Place objects up off the floor. Set object to carry downon a table or elevated surface instead of on the floor

Raise / lower shelves. The best zone for lifting is betweenyour shoulders and your waist. Put heavier objects onshelves at waist level, lighter objects on lower or highershelves.

Safe Lifting Techniques

Small light loads (one person lift)

Courtesy of: Imperial College, London

Moderately heavy loads (one person lift)

Courtesy of: Imperial College, London

Large Light Loads (One Person Lift)

Courtesy of: Imperial College, London

Moderately Heavy/Heavy Loads (2-person lift)

Courtesy of: Imperial College, London

Long Narrow Loads (One Person Lift)

Moving 5-leg chairs: one person lift

Courtesy of: Imperial College, London

Other Lifting Tips • Reduce the amount of weight to be lifted as much as

possible.

• Keep a clear view ahead when carrying/moving a load.Never carry a load in front of your face.

• Push a dolly or cart in a linear motion. Never pull, asit forces you to twist at the waist!

• Get help if the shape is too awkward or the object istoo heavy for you to lift and move by yourself!

• Know your body's limitations. Be aware of yourbody position at all times

• Learn to recognize situations where your back ismost at risk: bending, lifting, reaching, twisting,etc.

• Take measures to avoid an injury by using thistraining whenever you handle or lift materials

Practice Body Management

Safe Manual Handling Videohttp://ivle.nus.edu.sg/bank/media/viewmedia.aspx?Cha

nnelID=ad25a54e-107d-4a99-a777-f6b4e0d34908&MediaItemID=173ee5fb-fe88-4948-9399-a69a641d9a47&Player=WMP&Referrer=EC

Principles of Safe Lifting and Carrying Videohttp://ivle.nus.edu.sg/bank/media/viewmedia.aspx?Cha

nnelID=ad25a54e-107d-4a99-a777-f6b4e0d34908&MediaItemID=39fabf9d-38ab-4ff0-bccd-f17a881ad036&Player=WMP&Referrer=EC

Assignment• Download and print the Office Ergonomics Checklist

found at the OSHE Staff Portal, under “Ergonomics” tab.Fill out the checklist manually.

• For any ‘No’ ticks, fill out the necessarychanges/modifications to be adopted. If thechange/modification is missing from the list, proposeyour own under the ‘Comments’ column

• Only fill out the appropriate tool/equipment you use inthe laboratory. For tools/equipment not used, leave thatsection blank

• Scan checklist and email to: oshbaa@nus.edu.sg on orbefore May 23, 2012

• Only participants who completed the checklist will beawarded a Certificate of Completion

Office and Laboratory Ergonomics Manuals