The triangle on the care label

Short answer: The triangle on the care label is about bleaching. An empty triangle means any bleach may be used, while two diagonal lines inside allow only oxygen-based bleach without chlorine. That is the usual instruction on coloured clothes.

What an empty triangle allows

An empty triangle is rare and is found mostly on white cotton fabric meant for hard cleaning. The symbol says all kinds of bleach may be used. It does not appear on coloured items such as women's bamboo tops, so they should not be bleached. Always look at the symbol first.

The triangle with two lines

Two diagonal lines inside the triangle mean only oxygen-based bleach may be used, so no chlorine. That is the usual instruction on coloured clothes and on bamboo slips. The symbol is a limit, not an invitation to use bleach. It is mostly meant for cases where a white item needs extra help.

What chlorine does to fabric

Chlorine breaks down the fibres and turns them yellow over time, especially viscose. The damage creeps up and is often noticed only after several washes, when the fabric is worn and discoloured. So the two-line triangle must not be read as permission for chlorine. If you bleach, use oxygen-based only, and only if the label allows.

How gentle is oxygen bleach

Oxygen-based bleach is milder than chlorine, but it still weakens the fibres with repeated use. Use it only on whites and only a few times a year. Each time the fibres are strained, the fabric loses a little strength, so frequent bleaching is never a good choice. Look for another solution first.

Coloured clothes stay unbleached

Use no bleach at all on coloured fabric, because it attacks the colour and can cause stains. That also goes for bamboo sweat for men and women, where colour and elastic can both suffer. Two lines in the triangle do not mean coloured clothes should get oxygen bleach. It is only the upper limit of what the label allows.

Rarely needed

Bleach is rarely necessary. Sorting and correct dosing keep whites white, and that is far gentler on the fabric than bleaching every time. Wash whites on their own and use the amount of detergent stated on the pack. That way you avoid greyish tones without stressing the fibres through repeated treatments.

Sorting and dosing

Sort laundry by colour and temperature so whites do not pick up colour from other items. Stick to the amount of detergent on the pack, since too much can leave residue. Do not overfill the machine, so the water can rinse the soap out again. This is a much better habit than reaching for bleach.

Read the label first

Always read the triangle before choosing detergent or stain remover. If the triangle is empty you may choose freely, otherwise follow what the symbol says. If it is crossed out, no bleach may be used at all. To be safe, choose a mild detergent without bleach and let soaking time do the work.

Frequently asked questions

What does chlorine do to fabric

Chlorine breaks down the fibres and turns them yellow over time, especially viscose. The damage creeps up and cannot be repaired, so avoid it on all clothes.

Is oxygen-based bleach gentle

Milder, but it still weakens the fibres with repeated use. Use it only on whites and only a few times a year, and never on coloured fabric.

Is bleach necessary

Rarely. Sorting and correct dosing keep whites white. Wash whites on their own, follow the dosing on the pack, and make bleach an exception rather than a habit.