Swimwear Chlorine, Saltwater and Colorfastness Tests

Short answer: Do not approve swimwear from a “chlorine-resistant” fabric label alone. Put the exact standard and edition, specimen stage, exposure condition, reportable rating, pass requirement, color/print coverage and after-exposure physical checks in the test request. ISO 105-E03 covers colour fastness to chlorinated swimming-pool water; ISO 105-E02 covers colour fastness to sea water. Neither by itself proves elastane durability, seam recovery, sunscreen resistance or UPF, so those claims need separate agreed evidence.

Linked Sourcing supports two different ordering routes:

• Ready Styles from 50 pieces per style: choose an existing style, standard fabric and available size/color mix from the current private Excel catalogue. Ask Jerry for the stock quotation sheet and any current test evidence tied to the exact selected product. Request the Ready Styles files.
• Full Custom Manufacturing from 200 pieces per color and style: define the fabric, colors, prints, lining, elastics, trims, test methods and pass criteria before bulk approval. Start a Full Custom swimwear inquiry.

Testing scope can add sample consumption, laboratory cost and lead time. Set it before the purchase order or bulk fabric approval rather than deciding what “pass” means after seeing a report.

The core swimwear test matrix

“Colorfastness” is a family of questions, not one test. The methods below are current official ISO references checked on August 11, 2026. The purchase order should still lock the edition used by the appointed laboratory.

ISO lists ISO 105-X12:2016 as published but under systematic review on this article’s review date. If rubbing is part of an order placed later, reconfirm the current edition before issuing the laboratory request.

Chlorinated-water colour fastness: what ISO 105-E03 answers

ISO 105-E03:2010 is specifically titled “Colour fastness to chlorinated water (swimming-pool water).” ISO states that it evaluates the action of active chlorine at concentrations used for pool-water disinfection. Its public abstract lists three alternative conditions: 50 mg/l and 100 mg/l active chlorine for swimwear, and 20 mg/l for accessories such as beach robes and towels.

That does not mean a buyer can write only “ISO 105-E03 pass.” The request must identify:

• the standard and edition;
• which specified condition applies;
• whether the specimen is fabric, print, lining, trim or finished garment;
• the exact colorway and production identity;
• the required colour-change rating;
• any required staining assessment;
• whether physical performance is checked after exposure;
• the failure and retest rule.

Do not convert the ISO test concentration into a marketing claim about a number of pool visits. A laboratory condition is controlled evidence for a stated method; it is not automatically a consumer-use lifetime prediction.

Chlorine colourfastness is not chlorine durability

A fabric can retain an acceptable shade while losing stretch recovery, or keep its dimensions while a print, elastic or bonded edge deteriorates. Separate the visible colour question from the physical-function questions.

Depending on the product claim and construction, the written plan may need post-exposure checks for:

• fabric growth and recovery;
• waistband, leg-opening or strap elastic recovery;
• seam extension and seam integrity;
• opacity at an agreed stretch;
• print cracking, peeling or loss of adhesion;
• bonded-edge, adhesive or trim integrity;
• lining, thread and contrast-panel staining;
• tensile, bursting or other strength properties selected by a qualified laboratory.

The method, number of exposure cycles, conditioning, measurement points and pass limits must be agreed. Do not invent a universal “chlorine-resistant” physical test from a colorfastness report.

Sea-water colour fastness is a separate approval

ISO 105-E02:2013 covers resistance of textile colour to immersion in sea water. ISO confirmed this edition in 2023. It answers a different question from chlorinated pool water, so an E03 report cannot stand in for E02 and an E02 report cannot stand in for E03.

Sea-water testing also does not reproduce every beach-use condition. Sunscreen, body oil, heat, wet storage, abrasion by sand, repeated daylight exposure and washing can interact with a garment in real use. If a brand makes a specific resistance or durability claim, give the laboratory a written scenario and ask which validated method or buyer protocol can support it.

For contrast designs, identify what can stain what: dark outer fabric against a pale lining, printed panels against solid panels, binding against the body, and removable pads inside a wet garment. A report that names only “blue fabric” without the adjacent material or exact specimen identity is weak purchasing evidence.

Colour change, staining and rubbing are different results

Buyers often receive a single grade with no explanation. Require the report to distinguish:

1. Colour change — how the tested specimen changed compared with the untreated reference.
2. Staining — how much colour transferred to the specified adjacent fabric.
3. Rubbing transfer — how much colour moved to a dry or wet rubbing cloth under the rubbing method.
4. Physical damage — whether stretch, strength, seams, elastics, prints or trims changed after exposure.

ISO 105-A02:1993, confirmed current in 2025, describes the grey scale used for assessing colour change. ISO 105-A03:2019, confirmed current in 2025, describes the grey scale used for assessing staining. A test report should say which assessment applies rather than showing an unexplained number.

There is no one pass grade that Linked Sourcing should impose on every buyer. Requirements can differ by brand manual, destination, shade, end use and claim. Write the minimum rating before testing and keep colour change and staining as separate acceptance fields.

Laundering, rubbing, perspiration and light complete the picture

Pool and sea-water tests do not replace ordinary wear-and-care testing.

Laundering

ISO 105-C06:2010 covers specified domestic and commercial laundering procedures using a reference detergent. ISO reconfirmed it in April 2026. Its public abstract explains that single and multiple procedures do not represent the same severity, so the report must identify the procedure used. Also check dimensional change, print/trim durability and appearance with their appropriate methods; colourfastness alone does not approve them.

Wet and dry rubbing

ISO 105-X12:2016 allows dry and wet rubbing tests. Wet transfer matters for a garment worn against skin, towels, cover-ups or pale linings. State both required conditions when both are relevant, and identify whether a print, solid dye, lining or trim is tested.

Perspiration

ISO 105-E04:2013 assesses resistance of textile colour to human perspiration. It is relevant to swim tops, one-pieces and resort pieces that are also worn for active use. It does not simulate sunscreen or chlorine.

Artificial light

ISO 105-B02:2014 evaluates colour response to artificial light representative of daylight. This is a colourfastness test, not a UPF test. If a brand makes a UV-protection claim, use the destination market’s applicable UV-transmittance and labeling requirements separately.

The standalone activewear UPF and UV-protection testing guide explains the AATCC/ASTM, BS EN and AS/NZS routes, wet and stretched states, garment coverage and claim scope. A swim fabric’s UPF result does not by itself approve a low-coverage garment or prove chlorine, saltwater or sunscreen durability.

The standalone activewear washing, rubbing and perspiration colorfastness guide adds AATCC alternatives, explains color change versus staining/crocking ratings and provides a 20-field request for general activewear. Pool and sea-water exposure remain separate swimwear decisions.

Why fabric composition does not guarantee the result

“Nylon/spandex,” “polyester/elastane,” “recycled” and a GSM value describe parts of a material specification. They do not prove one colorway’s dye stability, one print’s adhesion, one elastic’s recovery or one finished garment’s durability.

Performance can change with:

• fiber and yarn system;
• elastane type and percentage;
• knit construction, density and heat setting;
• dye class, recipe and finishing;
• print chemistry and curing;
• lining, thread, elastic, pad and trim materials;
• pale, dark, neon and fluorescent colorways;
• bulk shade lot and process variation;
• exposure, washing and drying conditions.

Use the activewear fabric weight and stretch guide to specify GSM, stretch, power, growth and recovery as separate controls. A strong sourcing file connects the material specification to a traceable test report; it does not treat composition as a substitute for results.

Which colors and components should be tested

Avoid two extremes: testing one convenient black swatch for an entire collection, or testing every possible combination without a risk rationale.

Build a coverage matrix around:

• every new dye or print recipe;
• darkest shades and shades with known transfer risk;
• neons, fluorescents and difficult bright colors;
• dark-to-white or dark-to-pale contrast combinations;
• outer fabric, lining, binding, elastic, thread, pads and trims where relevant;
• digital, sublimation, screen, transfer or other print processes used;
• materially different fabric suppliers or constructions;
• different bulk shade lots when traceability or variation requires it;
• product claims and destination-buyer requirements.

The report should identify the style, material code, supplier or mill reference when available, color code, lot/batch, print version, specimen stage and test date. “Swim fabric passed” is not enough to connect a report to an order.

Test at the right development stage

Laboratory testing and AQL final inspection answer different questions. A final visual sample cannot prove chemical exposure performance, and a fabric report cannot prove that the finished lot has correct seams, measurements, labels or packaging.

The 14-field laboratory request

Send the laboratory or manufacturer a controlled request containing:

1. buyer, supplier and purchase-order identity;
2. product and intended-use description;
3. destination market and relevant buyer manual;
4. exact standard, part and edition;
5. selected condition or procedure within the method;
6. fabric, style, color, print and component codes;
7. batch, dye lot or bulk-lot identity;
8. specimen stage: fabric, component or finished garment;
9. preconditioning or prior laundering, if required;
10. colour-change and staining assessments required;
11. physical checks required after exposure;
12. numeric or grade pass criteria defined before testing;
13. report format, photos and traceability documents;
14. failure, corrective-action and retest rule.

For a Full Custom project, place these requirements in the testing section of the activewear tech pack. Keep the test request, laboratory report, approved sample and bulk release in the same revision-controlled approval file.

How to read a laboratory report before approving bulk

Check more than the word “PASS.” Verify:

• laboratory identity and report number;
• issue date and page count;
• applicant, manufacturer or supplier identity as applicable;
• specimen description and photographs;
• material, style, color and batch identifiers;
• method number, edition and condition;
• result for every required field;
• buyer requirement or pass limit used;
• deviations, exclusions, subcontracted tests and comments;
• whether the tested specimen is actually the one used in the order.

A report can be authentic but irrelevant to your purchase if it covers a different color, supplier, fabric construction or old batch. Ask for the chain between report, approved material and bulk-lot release.

Common swimwear testing mistakes

1. Writing only “ISO colorfastness.” The ISO 105 family contains different parts for different exposures.
2. Treating E03 as a durability guarantee. It is a colour-fastness method, not proof of every chlorine-related product claim.
3. Using sea water as a substitute for pool water. E02 and E03 answer different questions.
4. Approving one color for all colors. Dye and print recipes can behave differently.
5. Ignoring linings and contrast panels. Staining can make a garment commercially unacceptable even if the outer shade changes little.
6. Accepting an untraceable report. A result without material, color and batch identity cannot reliably release bulk.
7. Choosing the pass grade after testing. Acceptance criteria must be agreed before the result is known.
8. Calling artificial-light testing a UPF result. Fading resistance and UV protection are different claims.
9. Using a mill statement as finished-garment approval. Seams, elastic, prints, linings and trims may introduce new risks.
10. Skipping failure rules. Decide whether failure means hold, corrective action, replacement, retest or buyer review.

Ready Styles test request — MOQ 50

Ready Styles use an existing design, standard material and available size/color range. They are not an automatic promise that every color is in finished stock or that every historical report applies to the current lot.

Hi Jerry, please send the current private Ready Styles Excel catalogue and stock quotation sheet. I am looking for ____ swimwear styles, approximately ____ pieces per style, for the ____ market. After I select the styles, please confirm the available colors/sizes, fabric and lot identity, and whether current chlorine, sea-water or other colorfastness reports are available for the exact selected products. If new testing is needed, please quote the sample requirement, cost and timing before order confirmation.

Ready Styles start from 50 pieces per style, with at least 15 pieces for each selected color and size combination. Existing specifications are used. A new custom fabric, color, print or performance program should be evaluated under Full Custom Manufacturing. Request the current Ready Styles catalogue.

Full Custom swimwear brief — MOQ 200

Full Custom allows the test plan to be built into material and product development.

Hi Jerry, I want to develop a custom ____. Quantity: ____ pieces per color and style. Target market and use: ____. Fabric/lining/elastic/print requirements: ____. Required standards and editions: ____. Test conditions and pass grades: ____. Colorways/components to cover: ____. Post-exposure physical checks: ____. Third-party laboratory or buyer-manual requirements: ____. Please review test cost, sample consumption and timing before sampling and bulk approval.

Full Custom Manufacturing starts from 200 pieces per color and style. Special test programs, certified materials, custom trims, custom colors or technically demanding constructions can require additional cost, lead time or a higher material minimum. Start a Full Custom swimwear inquiry.

Standards and source scope

This guide was reviewed against the following official ISO pages on August 11, 2026:

• ISO 105-E03:2010 — colour fastness to chlorinated swimming-pool water; ISO confirmed the edition in 2026;
• ISO 105-E02:2013 — colour fastness to sea water; confirmed in 2023;
• ISO 105-C06:2010 — colour fastness to domestic and commercial laundering; reconfirmed in 2026;
• ISO 105-X12:2016 — colour fastness to dry and wet rubbing; published and under systematic review on the review date;
• ISO 105-E04:2013 — colour fastness to perspiration; confirmed in 2023;
• ISO 105-B02:2014 — colour fastness to artificial light using a xenon-arc source; confirmed in 2025;
• ISO 105-A02:1993 and ISO 105-A03:2019 — grey scales for assessing colour change and staining.

ISO method titles and public abstracts establish scope; the licensed standards and the appointed laboratory control the full procedure. This guide does not reproduce copyrighted test instructions, set one universal buyer pass grade or claim that Linked Sourcing has already tested every style, color, component or production lot.