Design is human centred and, therefore, designers need to ensure that the products they design are the right size for the user
Human Factors
The combination of ergonomics and anthropometrics
Aims of Human Factors
Reduce stress and fatigue on people, as they will be able to do things faster, more easily, more safely and make fewer mistakes (reduce errors)
Increase safety
Increase ease of use
Enhance operational comfort
Improve system performance, reliability and maintenance
Ergonomics
The application of scientific information concerning the relationship of human beings to the design of objects, systems and environments
Physical ergonomics
Deals with work related subjects of: posture; worksite development operating layout; material handling; repetitive stress and movement; repetitive stress injuries and musculoskeletal disorders; and occupational safety and health
Cognitive ergonomics
Concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system
Organisational ergonomics
Subjects include communication, work design, shift (work hours) management, crew resource management, teamwork, virtual organizations, telework, and quality management
Anthropometric data
Sub-classified as Static Data and Dynamic Data
Structural Anthropometric data
Static Data refers to measurements taken while the subject is in a fixed or standard position, e.g. height, arm length
Functional Anthropometric data
Dynamic Data refers to measurements taken during physical activities, e.g. crawling height, overhead reach and a range of upper body movements
Tell you whether the measurement given in the tables relates to the 'average' person, or someone who is above or below average in a certain dimension
Clearance
The minimum distance required to, enable the user group into or through an area
Reach
Also known as the workspace envelope, a 3-dimensional space within which you carry out physical work activities when you are at a fixed location
Adjustability
Certain products tend to be available in different sizes or with adjustability built in as there really is no 'one size fits all'
Range of sizes versus adjustability
Clothing comes in a range of sizes, while children's car seats are adjustable to allow for a range of sizes and a growing child
Ergonome
A 2D scaled physical anthropometric model based on a specific percentile human forms
Manikin
An anatomical3D model of the human body, a jointed model of the human body used by artists, especially to demonstrate the arrangement of drapery
Human beings vary psychologically in complex ways. Any attempt by designers to classify people into groups merely results in a statement of broad principles that may or may not be relevant to the individual
Cognitive psychology / cognitive ergonomics
Concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system
Methods for collecting Psychological factor data
Observation
Surveys & Interviews
Standardized Testing
Case Studies
Nominal Data Scale
Used in classification or division of objects into discrete groups, each of which is identified with a name. The scale does not provide any measurement within or between the categories
Ordinal Data Scale
Deals with the order or position of items. Words, letters, symbols or numbers arranged in a hierarchical order. Quantitative assessment can not be made
Interval data scale
Organised into even divisions or intervals. The intervals are of equal size. There is no zero
Ratio data scale
The difference between a ratio scale and an interval scale is that the zero point on an interval scale is some arbitrarily agreed value, whereas on a ratio scale it is a true zero
0°C has been defined arbitrarily as the freezing temperature of water, whereas 0 grams is a true zero, that is, no mass
A ratio scale allows you to compare differences between numbers
Psychological factors
Smell
Light
Sound
Taste
Texture
Temperature
Value
Smell
Important in food, perfumes, candles, deodorants, chemicals. Unpleasant odors are added to chemicals to warn people
Light
The level of illumination should increase as the tasks becomes more precise; for example the illumination required for a surgeon is brighter than the illumination needed for a corridor
Sound
Can be used to provide information such as warning signals, provide feedback that a product is working, and can be positive or negative in the environment
Taste
Important in food, it must have a good taste to sell well. Responses to taste are also a factor of culture and experience
Texture
Shapes and textures improve products and make them easier to use, for example bottle tops, handles fabrics and non-slip floors, smooth worktops in kitchen
Temperature
Clothing is an important part of a comfortable work environment but the environment must be controlled regardless of the outside climate. How the user responds to different environmental factors, for example, how warm or cold work environments can affect the performance of an individual. A range of comfort zones will exist based on body mass, manner of dress or even physiological changes that can be developed from exposure to a particular temperature or environment over time
Value
May be perceived as a function of cost, features, prestige, rarity etc. or a combination of these factors
Human information processing systems
Considering inputs, processes (sensory, central and motor) and outputs
Environmental factors
Noise
Lighting
Temperature
Humidity
Vibration
Breakdown with the Human information processing systems
Age
Skills level
Disability
Infirmity or frailty
Young children may not have the size, strength, fine motor control or skill to perform the tasks