The dots on a care label are just a rough guide
They are specific numbers. The standards body's table gives exact temperatures for every dot, and a bar under a symbol changes the process rather than the heat.
What is claimed
That the dots and bars on a care label are a general indication of severity rather than defined values, so a garment can be treated approximately.
Where this comes from: Traditional household practice.
Does it work?
Does not work
Refuted by the originating body's own table, which assigns a defined value to every variant — including the bar, which changes the process rather than the temperature.
This is a verdict on whether the technique is effective. Whether it is safe on a particular surface is a separate question, answered below.
Precautions
- Check the manufacturer's instructions
Why it works
The symbols are pictograms without printed numbers, so they read as qualitative. The table behind them assigns each variant a defined maximum temperature or a defined process severity, which is what allows one label to be honoured on any machine in any country.
Background
Care symbols are widely treated as approximate — more dots meaning hotter, roughly. The originating body's table is not approximate at all. Ironing dots correspond to stated maximum SOLE PLATE temperatures of 200°C, 150°C and 110°C, the last without steam, with the number of dots indicating severity. Tumble drying gives a normal temperature of 80°C and a lower temperature of 60°C, with dots again indicating severity, alongside a distinct do-not-tumble-dry symbol. Washing numbers in the tub are maximum temperatures, and processes are additionally labelled normal, mild and very mild. The part almost nobody knows is the bar: a BAR UNDER A CARE SYMBOL INDICATES A MILD PROCESS, and a DOUBLE BAR a very mild one. That is a statement about mechanical action and spin rather than about temperature, so two labels showing the same number can be asking for different treatment. Natural drying is equally specific, distinguishing line, drip line, flat and drip flat drying, each with an in-the-shade variant.
What it does not do
- The values are maxima the article can withstand, not recommended settings
- The table is the symbol system; a specific garment's label still governs that garment
What to use instead
- Wool detergent — A mild, near-neutral detergent without enzymes or bleach. What the wool industry body recommends, and what it recommends against is the more useful half.
Evidence
Does not work
Sources
GINETEX, The International Association for Textile Care Labelling · Standards body
Relied on for: That ironing gives maximum sole plate temperatures of 200°C, 150°C and 110°C without steam with dots indicating severity, that tumble drying gives 80°C normal and 60°C lower, and that a bar under a symbol indicates a mild process and a double bar a very mild process. (states this directly)
GINETEX Technical Booklet — international care labelling system
GINETEX, The International Association for Textile Care Labelling, 2018 · Standards body
Relied on for: That the symbols indicate the maximum severity of treatment an article can withstand without irreversible damage. (states this directly)