Oxygen bleach is the wool-safe bleach

Does it work?

Does not work

Refuted as to the specific claim that oxygen bleach is permissible on wool, on the direct instruction of the global industry body for the fibre. No authority takes the contrary position: the belief is inferred from the product's general reputation rather than asserted by anyone with standing.

This is a verdict on whether the technique is effective. Whether it is safe on a particular surface is a separate question, answered below.

Where not to use it

The proposed mechanism

The explanation below is what is offered for this technique. No evidence establishes that this is what actually happens, so treat it as a plausible story rather than as a finding.

The claim's reasoning is that hypochlorite damages wool through aggressive oxidation of the keratin, and that a milder oxidant will therefore act on the stain without reaching the fibre. The chemistry of the premise is sound as far as it goes: peroxide-based bleaches are weaker oxidants and are more selective towards fabric dyes than hypochlorite. What does not follow is the conclusion, because selectivity between a stain's chromophore and a garment's dye is a different question from selectivity between a stain and a protein fibre, and the wool industry body draws no distinction between the two bleach types when it advises against them. No mechanism-level account of why oxygen bleach is also advised against is available, because Woolmark gives none.

Background

Oxygen bleach is genuinely milder than chlorine bleach, genuinely more selective towards fabric dyes, and genuinely free of the chlorine-gas hazard. From those three true things a fourth is widely inferred: that it is therefore the bleach you may use on delicate protein fibres where chlorine bleach is prohibited. The Woolmark Company's guidance does not support that inference. Its instruction is to never use bleach when washing wool, chlorine-based or oxygen-based, and to avoid any detergent containing bleaches. The wool body advises against both chlorine and oxygen bleach, which is the opposite of what percarbonate's colour-safe reputation implies. A belief held as a precaution is more durable than an ordinary myth — nobody stress-tests the cautious option — and the marketing around percarbonate actively reinforces this one.

What it does not do

• The wool body advises against both bleach types and gives no mechanism for it, and no other authority addresses the question
• This says nothing about oxygen bleach on cotton or synthetics, where the position is different
• The care label for a specific garment governs, and may be more restrictive still

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.
• Neutral cleaner — A near-neutral surfactant cleaner. The recommended answer for natural stone of every kind, and the least interesting product in the cupboard for good reasons.