IB MYP Design – Sustainable and ethical design Revision Notes

For full explanations and worked examples, read the sustainable and ethical design study guide first. Then test yourself with the practice questions.

These notes are for IB MYP Design, aligned to the International Baccalaureate Organization, Middle Years Programme Subject Brief – Design, from 2014. They suit MYP years 4 and 5; MYP has no SL/HL split. MYP has no prescribed content list – schools design their own units – so these notes cover two related concepts the brief names for design (sustainability and ergonomics) plus data ethics, and how they feed criteria A and D. Your teacher will share the task-specific clarifications for each criterion.

Course links: course hub, printable checklist, assessment revision notes, design cycle revision notes, ePortfolio preparation.

What the brief says (IB facts only)

• Related concepts named as examples for design: adaptation, ergonomics, sustainability, innovation.
• Global contexts include Globalization and sustainability and Fairness and development.
• The aims include appreciating the impact of design on life, global society and environments, and acting with integrity and taking responsibility for your own actions.
• Criterion A: analyse the need for a solution and inquire into the nature of the problem.
• Criterion D: evaluate the solution’s success and explain its impact on the client or target audience.
• Each criterion has eight achievement levels (1–8) in four bands.

Key definitions

Term	Meaning
Life cycle	Every stage of a product’s life: raw materials, manufacture, distribution, use, end of life
Cradle to grave	Assessing impact from extraction to disposal
Cradle to cradle	Designing so end-of-life materials become new raw materials
Functional unit	The job used to compare products fairly (e.g. one year of use)
Embodied energy	Energy used to extract, process and make a material or product
Design for disassembly	Joining parts so they separate easily for repair or recycling
Planned obsolescence	Designing a product to become unusable or outdated sooner than necessary
Anthropometrics	Measurements of human body size
Percentile	The value below which that percentage of a group falls
Inclusive (universal) design	Designing for the widest range of users without special adaptation
Data minimisation	Collecting only the personal data a solution needs
Informed consent	A user’s clear, informed agreement before data is collected
Dark pattern	An interface trick that pushes users into choices they did not intend

Life cycle in one line each

1. Raw materials – extraction, refining, finite or renewable source.
2. Manufacture – processes, energy, waste offcuts, packaging.
3. Distribution – mass, volume, distance, transport type.
4. Use – energy, water, consumables, cleaning, repair, updates.
5. End of life – reuse, repair, recycle, compost, incinerate, landfill.

The 6 Rs: rethink, refuse, reduce, reuse, repair, recycle.

Method in steps: comparing two products’ life cycles

1. Choose one measure (e.g. energy in MJ) and one functional unit (e.g. per year).
2. Add up each product’s stages. Multiply per-year use figures by the lifespan.
3. Divide each total by the functional unit.
4. Name the largest stage for each – that is where redesign pays most.
5. State the assumptions (lifespan, number of uses) and what would change the result.

Break-even for reusable against single-use: reusable total = embodied + (per-use cost × n); single-use total = per-item cost × n. Set them equal and solve for n.

Worked reminder (fictional): a reusable cup costs 30 MJ to make plus 0.2 MJ per wash; a disposable cup costs 1.4 MJ each. 30 + 0.2n = 1.4n gives n = 30 ÷ 1.2 = 25. The two are equal at 25 uses; the reusable cup is lower from the 26th use.

Materials: must-know trade-offs

Material group	Sustainability plus	Sustainability minus
Timber	Renewable; certified sources (e.g. FSC)	Only renewable if forests are managed; finishes can be toxic
Metals (steel, aluminium)	Recycle repeatedly without losing properties	High energy from ore; mining impacts
Thermoplastics (PET, HDPE, PP)	Can be remelted and recycled	Finite oil source; mixed or dirty plastics often not recycled
Thermosets	Durable, heat resistant	Cannot be remelted
Bioplastics (PLA)	Plant source	Usually needs industrial composting; contaminates plastic recycling
Composites	Strong and light	Hard to separate at end of life

Method in steps: weighted decision matrix

1. List criteria from your research (function, sustainability, cost).
2. Give each a weight and justify it from the client’s need.
3. Score each material 1–5 on each criterion.
4. Multiply and add. The highest total is your provisional choice.
5. Check sensitivity: would a small change of weight change the winner? Say so.

Ergonomics

• Anthropometric data: body sizes. Physiological: strength, fatigue, comfort. Psychological: perception, feedback, clarity.
• 5th to 95th percentile covers 90% of the group.
• Clearance (openings, headroom, handle gaps) → 95th percentile, so large users fit.
• Reach (shelves, controls, pedals) → 5th percentile, so small users can reach.
• Adjustable range → from 5th to 95th percentile, plus allowances (shoes, clothing).
• Match the data set to the target audience (age, region, gender mix).

Worked reminder (fictional): 95th percentile hand breadth 92 mm, 8 mm clearance each side. Internal handle length = 92 + 2 × 8 = 108 mm.

Inclusive design checklist

The seven principles of universal design: equitable use; flexibility in use; simple and intuitive use; perceptible information; tolerance for error; low physical effort; size and space for approach and use.

• Two channels for important information (sound and light; icon and text).
• High contrast; never colour alone.
• Low forces; large grips; lever handles.
• Digital: follow WCAG – text alternatives, keyboard access, captions, readable contrast.

Data ethics in digital design

Principle	What it looks like in your solution
Minimisation	Only fields the solution needs; no “just in case” data
Informed consent	Plain-language notice; unticked opt-in box
Security	Passwords hashed, access controlled, data encrypted where possible
Transparency and control	Users can view, correct and delete their data
No manipulation	No hidden cancel buttons or pressuring pop-ups
Fairness	Test with a varied group to catch bias

Must-know distinctions

• Recyclable (can be recycled) is not recycled (contains recycled material).
• Biodegradable (breaks down eventually, in some conditions) is not compostable (breaks down in stated composting conditions).
• Total impact is not impact per functional unit.
• Design for the extreme (one limit) is not design for adjustability (a range).
• Anonymous data (cannot identify anyone) is not private data (identifiable, but protected).
• Accessible (usable by people with disabilities) is part of inclusive (usable by the widest range of people).

Feeding criteria A and D

Criterion A research questions: Which life-cycle stage of existing products has the largest impact? What materials do they use and where do they end up? Which percentiles matter for each dimension of my product? Who is excluded by current products? What data does a digital solution need, and what should it refuse to collect?

Criterion D impact statement formula: what changed for the user + evidence from testing + a sustainability or ethical consequence + one honest limitation.

Quick self-test

1. Name the five life-cycle stages in order.
2. Why must products with different lifespans be compared per functional unit?
3. A 12 kg product contains 35% recycled material by mass. What mass is recycled?
4. Kettle A: 120 MJ over a 6-year life. Kettle B: 150 MJ over a 10-year life. Which has the lower impact per year?
5. A reusable cup: 30 MJ to make plus 0.2 MJ per wash. A disposable cup: 1.4 MJ each. After how many uses are they equal?
6. Which percentile do you use for a door height, and why?
7. Which percentile do you use for the height of a shelf everyone must reach?
8. What percentage of a group lies outside the 5th–95th percentile range?
9. A handle must fit a 95th percentile hand breadth of 92 mm with 8 mm clearance each side. Find the internal length.
10. Give two differences between “biodegradable” and “compostable”.
11. State two ways a sign-up screen could respect informed consent.
12. Name one dark pattern.

Answers

1. Raw materials, manufacture, distribution, use, end of life.
2. A longer-lasting product spreads its making impact over more years, so totals alone mislead.
3. 12 × 0.35 = 4.2 kg.
4. A: 120 ÷ 6 = 20 MJ per year. B: 150 ÷ 10 = 15 MJ per year. B is lower.
5. 30 + 0.2n = 1.4n, so n = 25 uses; after that the reusable cup is lower.
6. 95th percentile – a clearance must let the largest users through.
7. 5th percentile – a reach must suit the smallest users.
8. 10% (5% below, 5% above).
9. 92 + 2 × 8 = 108 mm.
10. Biodegradable gives no time or conditions; compostable means it breaks down within stated composting conditions and time. Some bioplastics are only compostable industrially.
11. Any two: explain in plain language what is collected and why; ask before collecting; leave opt-in boxes unticked; make it easy to refuse or withdraw.
12. Any one: a hidden or hard-to-find cancel button; pre-ticked consent boxes; confusing double negatives; repeated nagging pop-ups.

Where marks are usually lost

• Calling a product “eco-friendly” with no stage, measure or evidence.
• Comparing totals for products with different lifespans.
• Forgetting the use stage for products that consume energy – for a lamp or kettle it is often the biggest.
• Using the 50th percentile for a clearance or reach.
• Quoting anthropometric data for the wrong age group, or with no source.
• Presenting a decision matrix without justifying the weights.
• Listing inclusive-design principles without testing with varied users.
• Collecting personal data in a digital solution without explaining why it is needed.
• A criterion D impact statement that only praises the product and gives no limitation.

Official syllabus

International Baccalaureate Organization, Middle Years Programme Subject Brief – Design, from 2014 (published by the International Baccalaureate Organization, © 2015). The brief names ergonomics and sustainability as examples of related concepts; the design content in these notes is standard practice written by Marlbridge.