Key Idea: Ergonomics is the fit between people, products and environments. Improving it makes a product more efficient, usable, functional, effective or safe. Anthropometrics measures the body as a percentile range — static when still, dynamic when working. Reach comes from the SMALLEST user; clearance from the LARGEST. One product covers a range by adjusting or by coming in sizes. Physiology is what the body can do. Psychology is what the senses can carry.
Paper 1 — multiple choice
- Classify a measurement as static or dynamic
- Pick the percentile for a stated dimension
- Identify which of the five improvements a change delivers
- Name the physiological limit a failure ignores
Paper 2 — analysing a product
- Justify the percentile used for a named part
- Explain a workstation layout using reach zones
- Explain how the senses shape one product
- Explain two limitations a design ignores, with fixes
Carried into the design project
- Your own user research and personae
- The anthropometric data behind every dimension you set
- Justifying adjustability or a size range in your solution
Three of the seven statements are definitions, and a wrong definition loses marks all the way through a Paper 2 answer. Learn these as sentences, not as ideas.
| Term | Definition | What it gives the designer |
|---|---|---|
| Ergonomics | The relationship and interaction between people and the products, systems and environments they use | Three relationships to check, not one |
| Anthropometrics | The measurement of human physical dimensions, expressed in the percentile range | How big the user is, and how many a dimension excludes |
| Physiology | The study of the systems and biomechanics within the body — their responses, limitations and capabilities | What the user can DO, and for how long |
Reach comes from the smallest user. Clearance comes from the largest. If the shortest person can reach it, everyone can. If the largest person fits through it, everyone fits.
Which slice of the population each design decision serves. Step through it once before the exam.
🔒 Interactive diagram
Explore the labelled diagram, charts and maps for this topic in study mode.
| Decision | Sized from | Because |
|---|---|---|
| Shelf, control or pedal distance | 5th percentile | It must be reached |
| Force to open a lid or turn a dial | 5th percentile of strength | The weaker user must manage it |
| Doorway, legroom, seat width | 95th percentile | The user must fit through or into it |
| Door handle or light-switch height | 50th percentile | Being wrong either way is harmless |
| Control used every few seconds | Normal reach zone | A full stretch repeated is an injury |
| Control used twice a shift | Maximum reach zone | Frees the prime space for what is used constantly |
Important: Answering "more comfortable" instead of naming one of the five improvements. Giving a static example when asked for a dynamic one — arm length is static, grip reach in use is dynamic. Naming a physiological limit and stopping. The consequence and the fix carry the other marks.
Normal reach, maximum reach and clearance on one user — the layout question in one picture.
🔒 Interactive diagram
Explore the labelled diagram, charts and maps for this topic in study mode.
A hairdresser works standing at a chair for six hours a day, using scissors and a hairdryer. Explain how ergonomics applies to the design of the salon chair and the hairdryer.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
A city is choosing between two designs for a self-service parcel locker: one with all lockers between 0.9 m and 1.5 m from the ground, and one using the full height of the cabinet from 0.3 m to 2.0 m. Evaluate which better meets the needs of its users.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
A tumble dryer has a control panel on its top surface, a door handle on the front, and an end-of-cycle buzzer. Describe the anthropometric or physiological data needed for each.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
Define ergonomics.
Reach or clearance — which percentile for each?
Static or dynamic — how do you tell?
Name the five improvements good ergonomics delivers.
Name the six physiological limits.
Why should critical information use two senses?
Adjustability or a range of sizes — how do you choose?
Exam tips
- Write reach → 5th, clearance → 95th at the top of your paper. It answers a surprising share of this topic.
- Never answer "more comfortable". Name one of the five improvements and say for whom.
- In any product scenario, hunt for the environment — light, noise, gloves, temperature, space.
- Evaluate needs strengths, limitations and a judgement. An answer with no conclusion caps itself.
- For a physiological limit, give the consequence and the fix, not just the name.
- Name the actual measurement — popliteal height, forward grip reach — never "leg data".