People, Users &
Responsibility
Reconnect ergonomics, user-centred design, inclusive design and designer responsibility as one decision system.
By the end of class, you should be able to…
Connect human factors
Use anthropometrics, physiology and psychology together.
Connect UCD evidence
Link research, persona, usability and task analysis.
Design inclusively
Recognize where averages fail and extremes help.
Reason ethically
Consider safety, standards, community/environment and obsolescence.
Ergonomics
Dimensions, capabilities, limitations and senses.
UCD
Research real users, tasks and environments.
Inclusive design
Design for the widest practical audience.
Responsibility
Safety, community, environment and product life.
Static
Body dimensions measured in fixed positions.
Dynamic
Dimensions/ranges measured while people move or perform tasks.
Population factors
Age, gender, ethnicity and disability can affect anthropometric datasets and design decisions.
Percentile choice
5th, 50th or 5th–95th depends on the variable: reach, clearance, fit, adjustability, etc.
Accessible storage cabinet
A designer must decide shelf height, door swing, handle location and usable space.
Reach
Can the intended population access the control/object?
Clearance
Is there enough space for bodies, hands, mobility devices or movement?
Work envelope
What area can the user operate within safely and effectively?
Body capability
visual accuracycolour perceptionstrengthfatiguemuscle controlhearing thresholdsSensory input
smellsoundtouchtastevisionTranslate data
control sizefeedback modalitycontrastforce requiredtask durationPlan
Begin with research questions that target user, task and environment.
Use multiple methods
Field research, observation, interviews, questionnaires/surveys, focus groups and task analysis reveal different evidence.
Analyse
Turn data into user characteristics, behaviours, wants, needs and design requirements.
| Potential advantage | Potential limitation |
|---|---|
| Higher fit with real user needs | Time, recruitment and access to users can be difficult. |
| Problems appear through observation/testing | User feedback can conflict or represent only part of the population. |
| Iterative feedback improves usability | More iterations can increase cost/time. |
| Diverse evidence can reduce assumptions | Bias can still enter sampling, personas or interpretation. |
Primary persona
Evidence-based representation of target-user attributes used to guide decisions.
Scenario
A context/story showing how a user may interact with a product or task.
Population stereotype
Generalized expectations about a population; can speed early thinking but risks oversimplification/bias.
Five usability objectives
learnabilityefficiencymemorabilityerrorssatisfactionTask analysis
break task into stepsobserve critical pointsidentify pain pointslocate design opportunitiesUser journey
environmentmotivationinteractionexperience over timeWidest practical audience
Inclusive design targets broad accessibility across age/ability, including physical, sensory and cognitive impairments.
Average is not universal
The 50th-percentile adult/child is not automatically representative or appropriate for every design variable.
Design for extremes
Solving for users at capability extremes can create mainstream benefits for the general population.
Clients / community / environment
Design decisions can create positive or negative social/environmental impacts.
Safety + standards
Standards help protect user well-being, health and safety.
Obsolescence
Planned, social, style, functional and technological obsolescence affect the triple bottom line.
Responsibility ≠ perfection
Designers weigh competing needs and justify trade-offs.
Redesign a medication organizer for older adults.
Users report difficulty opening lids, reading labels and remembering the sequence.
Before you leave…
Process, Research & Prototyping — Synthesis
Keep the retrieval loop moving: recall → apply → check → correct → revisit.
Cumulative synthesis of A1.1 Ergonomics, B1.1 User-centred design, C1.1 Responsibility of the designer and C1.2 Inclusive design, including all required percentile, physiology/psychology, UCD research, usability, task analysis, safety/standards, obsolescence and design-for-extremes concepts.