In a dyehouse one worker can move from a caustic scour bath to a hypochlorite bleach, a reactive dye bath and an acid neutralisation in a single shift, often in one room. Recent months in South Asia show what that range of chemistry means when it is managed with one glove.
One Room, Four Chemistries
Scouring and mercerising run on sodium hydroxide at 20 to 30 percent, liquor at 80 to 98 degrees Celsius, pH near 14. Bleaching follows with sodium hypochlorite or hydrogen peroxide. Dyeing needs pH 10 to 11 and heavy electrolyte at similar heat. Reduction clearing uses sodium hydrosulfite, a self-heating solid that ignites on contact with air and releases sulphur dioxide. The bath is finally pulled to pH 4 or 5 with acetic or formic acid, and smaller units decant hydrochloric acid by hand. On 6 October, workers mixing that acid for yarn dyeing at a unit in Salem, southern India, noticed a release; more than fifty people in the unit and nearby houses reported eye irritation and breathing difficulty.
No thin glove spans that range, and that is the first design fact of the programme.
The Glove Is Chosen by the Bucket
Butyl rubber handles strong caustic well but is weak against some solvents. Nitrile is a sound general barrier yet swells after repeated hypochlorite contact. Laminated film gives the broadest coverage at the cost of grip on a wet hose. Assign a colour-coded glove to each step and hang the compatibility matrix beside the bath.
Where exposure happens matters. In Surat district on 1 September a chemical drum burst at a dyeing mill and started a fire; more than fifteen people were injured and the toll climbed to eight, with a negligence case filed against the drum operator and a shift supervisor. The person opening the drum stands in the splash zone, so the glove specification should begin from that task, not the average of the room.
Change rules matter more than ratings. A glove can look intact and be wet inside from sweat and condensate, and reactive dye powder is a skin sensitiser that a damp glove holds against the skin for hours. Rinse, dry inside out, replace on a count of dips or hours. Cotton and leather absorb liquor and hold heat, so neither belongs in a wet room.
Boots: The Only Reusable Item on a Wet Floor
Floors stay wet with alkaline liquor, surfactant and dye, and often hot. Slip figures from a dry tile mean nothing; ask for wet and soapy steel. EN 13832 assesses degradation rather than permeation, so a pass mark does not say how long a boot resists a 30 percent caustic splash; request compound-specific data at process temperature. Height counts: when an operator lifts a hose, liquor runs down the outside and enters at the top, so specify a boot that clears the knee.
Because boots are reused, management is the control: a washdown point at the exit, a drying rack, and a rule that softened or tacky material is scrapped rather than reassigned. In Panipat, northern India, a human rights commission took notice in October of bleaching units reported to operate without pollution consent and to issue no boots or gloves, with ten to twelve workers a day at the civil hospital with damaged hands, feet and skin allergy. That gap is a specification and a replacement budget, not product performance.
What to Put in the Specification
Four lines carry most of the risk: one glove per chemical step with a compatibility matrix tested at the line's own concentration and temperature; a stated change interval per shift; boots with wet-floor slip data and a written scrap rule; and enough sizes plus a drying cycle for the crew. A dyehouse buying one glove for four chemistries is not saving money. It defers a hospital visit.