The Stain Library

How to remove baby sick from a waterproof jacket

Published by The Stain Library. How we research our methods.

  • DifficultyEasy
  • OutlookUsually removable
  • MaterialWaterproof jacket
  • Reviewed7 September 2026

The short answer

Rinse the mark off under cold water, because a waterproof shell sheds most of a fresh spill anyway. If more is needed, use a small amount of liquid detergent, which is exactly what the membrane maker specifies. No powder detergent, no fabric softener, no stain remover and no bleach, because those strip the water repellent finish and bleach affects the performance of the garment.

If it has just happened

Hold the marked area under a cold tap. A waterproof shell is designed to shed liquid, so a fresh spill often rinses straight off with nothing else at all.

Avoid heat while treating the stain

Avoid adding heat while treating this stain. Follow the material's care instructions and the method below; heat may make a mark harder to remove or damage the material or its finish.

Test on a hidden area first

Use only a cleaner allowed by the material's care instructions. Test it on an inconspicuous area with the same material and finish, or a matching offcut. Let the test area dry and check for changes in colour, texture or finish before treating the visible mark.

Cleaning the mark is not the same as disinfecting

If the sickness came with a stomach bug rather than an ordinary posset, the surface may carry norovirus, which spreads easily and survives on hard surfaces. UK public health guidance is to wear gloves, avoid shaking contaminated laundry, wash affected laundry separately with normal powder at 60 C where the care label allows it, and disinfect compatible hard surfaces with a bleach based product afterwards. Do that after the stain work, not instead of it, and only where the material tolerates it.

Keep every kind of drying heat away until the mark has gone

Baby sick is mostly milk protein. Heat coagulates protein and locks it into the material, which is why a mark that would have washed out can become permanent after one hot wash, one pass with an iron, a hairdryer or a spell on a radiator. Cool or warm treatment, air drying, and a proper look in daylight before anything warm goes near it.

What you will need

  • Disposable gloves Sickness that came with a stomach bug is a hygiene job as well as a stain.
  • A spoon or blunt scraper For lifting solids off before any liquid is involved.
  • White cloths and kitchen roll White only, and several, so you can always fold to a clean face.
  • Cold water Cold. Heat sets milk protein, and every item in this family is heat sensitive as well.
  • Bicarbonate of soda The absorbent that draws moisture back out of a filling or a foam.
  • A fan Airflow is what dries a filled item. Heat is not available.

Fresh baby sick on waterproof jacket

The jacket is designed to shed liquid, so use that rather than reaching for a cleaner.

  1. Lift the solids off

    They will be sitting on the surface rather than in the fabric. A spoon or a cloth, and straight into a bag.

  2. Rinse the area under a cold tap

    Cold running water from the outside face. On a jacket with a working repellent finish this alone usually deals with a fresh mark.

  3. If more is needed, a small amount of liquid detergent

    On a cloth, not sprayed on. Liquid only, because the maker excludes powder detergents, and a small amount because residue is what clogs the finish.

  4. Rinse the detergent out and hang it to dry

    Rinse thoroughly with plain water, then hang the jacket somewhere airy. Do not put it near a radiator.

  • How longFive minutes
  • RepeatingRinse until nothing more comes off.
  • Stop ifthe shell is clean and rinsed with no detergent left in the fabric

Dried baby sick on waterproof jacket

A dried mark on a shell is on the surface, and washing the whole jacket is often tidier than treating a patch.

  1. Flake off what will come off dry

    Coated fabric releases dried milk readily. A fingernail or a soft brush takes most of it.

  2. Soften the rest with a cold damp cloth

    Hold it on for a minute rather than scrubbing. The residue is bonded to a coating, not absorbed into a fibre.

  3. Then wash the whole jacket rather than the patch

    A small amount of liquid detergent at 40 degrees, which is what the maker specifies. Washing the whole garment avoids the uneven repellency that a spot clean leaves.

  4. Reactivate the finish afterwards

    Once the mark has definitely gone, the maker's step to restore the water repellency is twenty minutes in a tumble dryer after line drying. Only do this after the stain is out.

  • How longTwenty minutes, or a wash cycle
  • RepeatingOne local attempt, then wash the whole jacket.
  • Stop ifthe mark has gone and the jacket has been rinsed of detergent

What not to use on waterproof jacket

  • Fabric softener, powder detergent, stain removers and bleach

    The membrane manufacturer excludes all four by name. Bleach is singled out as affecting the colour and the performance of the garment, and the others strip or clog the water repellent finish.

  • Tumble drying it before the mark has gone

    Heat sets milk protein. The tumble drying step exists to reactivate the repellent finish and belongs at the end of the process, not the beginning.

  • Scrubbing the face fabric with a brush

    Abrasion wears the repellent finish off in exactly the patch you are working on, and the jacket then wets out there first.

White compared with coloured waterproof jacket

The colour on a waterproof jacket is rarely at risk from a milk mark, and the maker warns about bleach affecting colour and performance together. The change you are more likely to notice is functional: a patch that has been cleaned with detergent stops beading water while the rest of the jacket still does, which shows as a dark wet area in rain. Rinsing the treated area thoroughly, or washing the whole jacket, evens that out.

If the mark is still there

If a mark survives a rinse, wash the whole jacket rather than treating the patch, because that avoids the uneven finish that spot cleaning leaves. The maker's specification is a small amount of liquid detergent at 40 degrees, and that is safe here because the mark has already been rinsed off rather than being baked in.

After washing, the water repellent finish usually needs reactivating, which the maker does with twenty minutes in a tumble dryer after line drying. If the jacket no longer beads water at all, it needs re-proofing with a wash in or spray on product rather than more washing.

If sick got inside the jacket, onto the membrane backing or the taped seams, an outdoor kit cleaning service is the right answer, because they clean and re-proof together.

When to stop and call someone

Use an outdoor kit cleaning service rather than continuing if the sick got inside the jacket onto the membrane backing or the taped seams, if the jacket has stopped beading water after cleaning, or if two plain washes have not shifted the mark. They can clean and re-proof in one go, which is what a jacket that has lost its finish actually needs.

Why baby sick behaves this way on waterproof jacket

A waterproof jacket is a laminate with a coating on the outside, and the coating is what you can damage.

The finish is the vulnerable layer

The durable water repellent treatment makes rain bead and roll off. Fabric softener coats it, detergent residue clogs it and stain removers strip it. Once it has gone the face fabric absorbs water, and the jacket feels cold and clammy and stops breathing, even though the membrane underneath is intact.

The maker's list is unusually short

Liquid detergent, a small amount, at 40 degrees, and nothing else. That short list is doing real work rather than being cautious.

Bleach is excluded for two reasons

The manufacturer says it affects both the colour and the performance of the garment. It is one of the few places where a maker names performance rather than appearance.

Heat has one legitimate use, at the end

Twenty minutes of tumble drying reactivates the finish after washing. That is a step for after the stain has gone, never before, because heat sets milk protein.

Sources

What we checked and when. Where a manufacturer instruction disagrees with anything here, follow the manufacturer.

  1. How to remove baby formula stains, Purex Stain Lab manufacturer

    Manufacturer guidance identifying breast milk, formula and baby spit-up as protein stains, explaining the role of enzymes, and warning that the mark should be checked before any drying heat because heat sets what remains.

    Checked 7 September 2026

  2. A guide to newborn laundry, American Cleaning Institute trade body

    Cleaning trade body guide to pre-treat breast milk, formula or spit-up with an enzyme stain remover, soak fresh marks for at least 30 minutes and older marks for several hours, launder, and keep stained items out of the dryer until the mark has gone.

    Checked 7 September 2026

  3. How to remove stains from baby clothes, Persil UK manufacturer

    UK manufacturer guidance to act quickly on formula, blot when immediate washing is impossible, rinse under cool water, soak for at least 15 minutes where the care label permits, pre-treat with detergent and then wash to the care label.

    Checked 7 September 2026

  4. Norovirus: what to do and how to stop the spread, UK Health Security Agency authority

    UK public health guidance establishing that illness related vomit can carry norovirus, that contaminated laundry should be washed with normal powder at 60 C where the care label permits, and that compatible hard surfaces should be disinfected with a bleach based product.

    Checked 7 September 2026