The dye bath going down the yard
A craft group of nine women in Rundu makes tie-dye and batik T-shirts for tourists. They work in a converted garage with one window and a roll-up door. They dye with reactive dyes using soda ash and salt in plastic buckets, and melt paraffin wax in an open saucepan on a two-plate electric stove for batik. Finished garments are rinsed in three buckets, and the used dye and rinse water are poured onto the yard, which slopes towards a communal standpipe about 15 m away. Fabric offcuts are burned in a drum behind the garage. Two members have itchy rashes on their hands and forearms, and one has headaches by mid-afternoon. A neighbour has complained about the smell and the coloured water. The group earns about N$6,000 a month and has N$800 to spend on improvements.
1. Identify four hazards in this workshop, rank them by risk, and choose a control for each that the group can actually afford.
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Hazards and ranking (likelihood x severity):
- Caustic soda and dye powder: splashes to the eyes can cause serious damage, and the dust irritates lungs. Severity high, likelihood moderate - the highest risk.
- Molten paraffin wax on an open stove: deep burns and fire, with no lid, thermometer or fire blanket. Severity very high, likelihood low-moderate.
- Poor ventilation: headaches, dizziness and skin problems from fumes and the humid, steamy room. Likelihood high, severity moderate.
- Dye and alkaline water running to the yard and standpipe: soil and water contamination plus conflict with neighbours. Severity moderate-high, likelihood certain.
Controls, using the hierarchy - eliminate or substitute first, PPE last:
- Caustic soda: buy it in small pre-measured sachets or keep it in one labelled, lidded bucket with a scoop that stays in the bucket; add soda to water, never water to soda; always wear nitrile gloves and goggles when mixing.
- Wax: replace the open saucepan with a thermostatically controlled wax pot or use a double boiler, keep a lid, a thermometer and a fire blanket within reach, and never leave melting wax unattended.
- Ventilation: a box fan at the door pulling air out and the window open, plus lidded buckets so vapours are not constantly开放 - simple, cheap and effective.
- Waste water: stop pouring to the yard immediately; see the waste plan. PPE is the last line, not the first: gloves, goggles and aprons protect, but they do not remove the hazard.
2. Design a water and waste plan for the group, covering the dye bath, the rinse water, the wax and the offcuts. Explain why the current disposal is unacceptable.
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Why it is unacceptable: the yard slopes to a communal standpipe, so coloured, strongly alkaline water (reactive dye baths sit around pH 11 with heavy salt loads) reaches the water people use. It can stain, contaminate soil and groundwater, kill plants, and it is a public health and neighbour-relations problem. Burning offcuts adds smoke and, if any synthetic scraps are mixed in, harmful fumes, plus a fire risk behind a wooden garage.
Plan:
- Exhaust the dye first: dye the darkest shade last and reuse the bath, adding a little dye, salt and soda for a second, darker batch. A used bath still has much of its dye; pouring it out is wasted money as well as pollution.
- Rinse counter-current: three buckets in a row, moving garments from dirty to clean, so the cleanest rinse water is used last. Reuse the first rinse as the next dyebath make-up water or for cleaning floors.
- Neutralise before disposal: let the bath cool, add vinegar or citric acid until it is close to neutral (test with litmus paper), then dispose to the sewer or septic system with plenty of water, never to the yard, a storm drain or near the standpipe. Check with the municipality on local rules.
- Wax: strain used wax through cloth and reuse it; cooled wax is not poured away.
- Offcuts: sort by fibre. Cotton scraps can be composted or given to weavers and patchwork makers; make scrunchies, headbands or patchwork panels from the rest. Nothing goes in the burn drum.
- Keep one labelled bucket for waste, not the yard.
3. How could the group turn these changes into a business advantage, and what would you say to members who argue that the changes cost too much?
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The changes cost less than the current losses: wasted dye and salt, water carried in buckets, sick days, and a neighbour who may report them. Frame the argument in money and in customers, not in scolding.
Business advantage:
- Story: tour lodges sell local, handmade, low-impact products. A simple swing tag - "hand-dyed in Rundu, dye baths reused, no chemicals to the yard" - supports a higher price. Even N$10 extra on 200 shirts a month is N$2,000.
- Consistency: lidded buckets, measured soda and a thermometer give repeatable colours, so fewer rejected shirts and fewer complaints.
- Health: fewer rashes and headaches means fewer days lost; two members already lose afternoon work.
- Cheaper inputs: reusing dyebaths and rinse water cuts dye, salt and water purchases.
- Market access: some buyers ask suppliers about waste and worker safety; being able to answer is a qualification, not a cost.
To the sceptic: propose a one-month trial, spend the N$800 on gloves, goggles, a box fan, a thermometer and a lidded waste bucket, and keep a simple record of dye used, shirts sold and sick days before and after. Numbers from their own workshop are far more persuasive than an outside opinion, and the record doubles as evidence for funding applications.