This mini-lesson covers the Viability of Design Solutions for OCR A-level Product Design: quality control and assurance, tolerances, marketing and the product life cycle, and costing and enterprise.
You will separate QC from QA, weigh niche and mass markets, and calculate a tolerance and a break-even. Press Start to begin.
Quality
Quality control and quality assurance
Two complementary ideas keep quality high:
Quality control (QC) — inspecting and testing products (or samples) to catch defects after they occur.
Quality assurance (QA) — building quality into the whole process so defects are prevented, often certified to ISO 9001.
The BSI Kitemark shows independently verified compliance with a standard.
Quick check
QC or QA?
?How do quality control (QC) and quality assurance (QA) differ?
Tolerances
Tolerances and testing
Parts are made to a permitted range:
Nominal size — the target dimension.
Upper and lower limits — largest and smallest acceptable sizes.
Tolerance = upper limit - lower limit.
Solutions are also judged by testing against the specification and by user feedback.
Calculate
Your turn — tolerance
1A part is specified as 25 ± 0.1 mm. Tolerance = upper limit - lower limit. Calculate the total tolerance.
mm
Hint: upper = 25.1, lower = 24.9, so 25.1 - 24.9.
Marketing
Marketing and the product life cycle
A product must be commercially viable:
Product life cycle — introduction, growth, maturity and decline; marketing and redesign can extend it.
Niche market — a small, specialised group; mass market — a large, general audience.
Branding and the marketing mix position a product against competitors.
Quick check
Niche or mass?
?A luxury, hand-finished audio product sells in small numbers to enthusiasts at a high price. Which market is this?
Costing
Costing, enterprise and feasibility
Viability rests on the numbers:
Fixed costs (tooling, rent) do not change with output; variable costs (materials, labour per unit) do.
Break-even quantity = fixed costs ÷ (selling price - variable cost). Below it the product makes a loss.
Profit margin and market size decide whether a solution is worth producing.
Calculate
Your turn — break-even
2A product has fixed costs of 3600, sells for 15 each and has a variable cost of 6 per unit. Break-even quantity = fixed costs ÷ (price - variable cost). Calculate the break-even quantity.
units
Hint: 3600 ÷ (15 - 6) = 3600 ÷ 9.
Sort it
Sort the viability factors
Tap a factor, then the group it belongs to.
✅ Quality (QC/QA)
📣 Marketing
💷 Costing / enterprise
Match it
Match each term to its meaning
Tap an item on the left, then its match on the right.
Term
Meaning
Recap
The big ideas to know
QC inspects to find defects; QA prevents them across the process (ISO 9001, BSI Kitemark)
Tolerance = upper limit - lower limit
Product life cycle: introduction, growth, maturity, decline
Markets: niche (small, specialised) vs mass (large, general)