Shrinkage Claim, Missing Care Label and Two Safety Incidents in a Training Unit
A vocational training centre's production unit has supplied 500 poly-viscose (65% polyester / 35% viscose) school trousers to a local school. Within a month the school reports that leg length has shrunk by about 3 cm after the first home wash at 60 °C followed by tumble drying, that seams pucker and pocket mouths gape, that navy dye has bled onto white shirts washed in the same load, and that the care label carries only the words 'Wash separately' with no fibre content or iron instruction. The unit's records show the fabric came from a mill with no shrink-resist finish and was cut the day after receipt without relaxation. Separately, a machinist sustained a needle injury to the index finger while back-tacking, and the ironing section has logged two steam burns this month. The unit has 12 machines, no needle guards, an unguarded belt drive and no written safety instruction. The school is asking for 90 trousers to be replaced.
1. Explain the shrinkage and the dye bleeding from the fibre properties, and state what the unit should have done at the fabric stage.
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Shrinkage
- Viscose has a low wet modulus: it swells strongly in water, loses strength when wet and relaxes back on drying, so the 35% viscose component is the main source of shrinkage. Polyester is hydrophobic and heat-set, so it contributes little - which is why the shrinkage shows as a differential effect and the seams pucker.
- Washing at 60 °C plus tumble drying adds relaxation shrinkage and, at high heat, thermal shrinkage in the polyester; the two together easily explain 3 cm on a trouser leg.
- Cutting the day after receipt means the fabric was still under weaving/finishing tension; it relaxed after cutting, so the cut parts were already shorter than intended.
Dye bleeding
- Viscose is dyed with direct or reactive dyes and polyester with disperse dyes. If the mill's soaping-off and reduction clearing were incomplete, unfixed dye sits on the fibre and bleeds in the first washes - hence the navy on the white shirts.
What should have been done
- Ask the mill for residual shrinkage figures and a wash-test report (ISO 6330 wash, ISO 5077 measurement); specify ≤2% and a colourfastness to washing of at least 4.
- Relax the fabric in open width (steam/decatise or 24–48 h conditioning) before cutting.
- Cut with a length allowance for the measured residual shrinkage, and wash-test a sewn sample before bulk cutting.
- Reject or re-process lots without a fastness report.
2. Draft the correct care label content for the trousers and justify each element.
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Label content
- Fibre content: 65% polyester, 35% viscose - mandatory, and the missing element that let the school assume the trousers were hard-wearing.
- Wash: machine wash at 40 °C, mild/synthetics cycle - 60 °C plus tumble drying exceeded the fabric's tolerance; 40 °C limits further relaxation shrinkage and dye loss.
- Do not bleach - chlorine degrades viscose and fades the navy.
- Do not tumble dry; line dry in shade - the single biggest cause of the 3 cm loss.
- Warm iron, max 150 °C, on the reverse - above this the polyester glazes and shines; viscose scorches easily, so a pressing cloth is advised.
- Wash dark colours separately / with similar colours for the first washes - reflects the measured bleeding risk.
- Dry cleanable (P) optional, for school-contract customers.
Justification approach
- A care label is a performance claim, not decoration: every instruction must be one the garment has been tested to survive. The label should be written from the wash-test report, not from the mill's general advice.
- Symbols must follow the standard system in use in the market (ISO 3758), with words in the language the buyer requires.
- Keep a labelled retained sample from the lot so any future claim can be tested against the stated instructions.
3. Recommend controls for the needle injury and the steam burns, and explain why the order of controls matters.
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Applying the hierarchy of control
- Eliminate / substitute: programme the back-tack on the machine so the operator does not place fingers near the needle; replace open steam irons with thermostatically controlled irons with insulated handles where possible.
- Engineering controls (highest value here): fit needle guards and finger guards on all 12 machines, guard the belt drive, fit a needle-plate hole of correct size, install local exhaust ventilation and a steam trap in the ironing section, and set iron thermostats to a fixed maximum.
- Administrative controls: written safe operating instructions at each machine, induction and refresher training, no loose jewellery or open footwear, a minimum two-second habit of removing the foot from the pedal before threading, an accident register and first-aid kit, a named safety supervisor, and a daily check sheet for guards.
- PPE: heat-resistant gloves for the ironing section and finger guards - but as the last line, because PPE protects only the person wearing it and fails silently.
Why the order matters
- A needle injury cannot be prevented by telling a machinist to be careful; the needle travels faster than reaction time. The guard works every cycle without relying on attention, so it must come before training or PPE.
- For steam burns the same logic applies: a fixed thermostat and insulated handle remove the hazard; gloves only reduce the severity.
- Record each incident with cause and corrective action - this is both a legal expectation under factory safety provisions and the evidence a buyer will ask for in a social-compliance audit.