Jan #4 - Industrial Ergonomics

Question 1

Define ergonomics

Answer 1

Ergonomics is a technology that seeks to improve mental and physical wellbeing by optimising the function of “human-machine-environment” systems to “fitting the task to the person”.

Question 2

Working conditions impact on productivity, product quality, and worker safety. What are the four main factors to be considered with respect to working conditions?

Answer 2

1. Temperature
2. Ventilation
3. Noise
4. Lighting

Question 3

Lighting is an important factor when considering working conditions. Define the following terms associated with lighting, and give their units: Illuminance, luminance, and luminous flux

Answer 3

Illuminance - amount of light falling on a surface, measured in Lux (where 1 Lux = 1 Lumen/m^2)

Luminance - amount of light emitted by objects or from surfaces (depends on reflectivity), with units of candela/m^2

Luminous flux - total amount of visible light present, measured in lumens.

Question 4

How can we account for lighting in the design of a working envvironment?

Answer 4

There are different recommended illumination levels for different activities, from 20-50 Lux in public areas with dark surroundings to 1500-2000 Lux for detailed drawing work. We also need to account for the deterioration of visual acuity with age.

Question 5

Noise induced hearing loss is painless, gradual, irreparable, and permanent. How do the effects of noise vary from below 80dB to above 115dB?

Answer 5

Below 80dB - no risk, regardless of exposure

80-90dB - risks limited to very long exposures

90-115dB - louder the sound, less time needed for damage to occur

Above 115dB - very brief sounds immediately cause irreversible damage

Question 6

The Health and Safety Act has set two exposure limits for noise. Describe these limits

Answer 6

1. Average level of 85dB over an 8 hour period
2. Peak level of 140dB

Question 7

List 4 ways by which the risk of Noise Induced Hearing Loss can be minimised

Answer 7

1. Control source of noise
2. Stopping noise from reaching people
3. Reducing time of exposure
4. Use individual protection (e.g. earmuffs)

Question 8

List 5 risk factors associated with musculoskeletal disorders in the work environment

Answer 8

Repetitive Motion

Forceful exertions

Awkward postures

Contact stress

Vibration

Question 9

What are the 10 principles of ergonomics?

Answer 9

Maintain: neutral postures, proper heights, and a comfortable environment

Minimise: excessive force, excessive motions, fatigue/static load, and pressure points

Provide Clearance

Move, exercise, and stretch

Question 10

Define the following three terms related to ergonomics: anthropometry, biomechanics, and work physiology

Answer 10

Anthropometry: workplace design to suit human operator

Biomechanics: Knowledge of acceptable exertions and human physical limitations to be expected for a job

Work physiology: ensuring provisions made for recovery from mentally/physically demanding work

Question 11

Define the following three terms related to ergonomics: environmental engineering (EE), skill psychology, and occupational psychology

Answer 11

EE: design/control of physical environment within which work is undertaken

Skill psychology: understanding/optimising exchange of information between operator and equipment

Occupational psychology: selection, training, and motivation of workers