Colorfastness to chlorinated pool water is a controlled assessment of whether a dyed, printed, or otherwise colored textile changes color after specified chlorine-water exposure. For buyers, approval should rest on a written method, selected exposure condition, identified colorways and components, a defined color-change threshold, and a report that matches the approved production material—not a broad “chlorine-resistant” description.
By Cherry Liu, Sales and Client Solutions
Define the approval question before selecting a test
A pool-exposure approval answers a narrow visual question: how much does the tested textile’s color change after the defined chlorinated-water exposure? It does not automatically approve a garment for every form of water use, every colorway, or an unlimited service life.
That boundary matters because buyers often combine several risks into one request. A black printed swim short, for example, may raise separate questions about body-fabric shade retention, print appearance, lining contrast, elastic recovery, seam performance, laundering, sunlight, sunscreen contact, and wet storage. A pool-colorfastness result should be used only for the color-change question it was designed to answer.
For product development, distinguish these terms clearly:
- Chlorinated pool-water colorfastness concerns color change following the specified pool-water exposure.
- Seawater exposure is a different use scenario. A pool-water result should not be treated as evidence for beach or saltwater performance.
- Laundry bleach exposure is not the same buyer question as controlled swimming-pool-water exposure. Care instructions and home-laundry risks need their own review.
- Water resistance concerns a garment’s resistance to water penetration or wetting. It is not a dye or print color-retention claim.
- Chlorine-proof suggests a much broader and potentially enduring promise than a single colorfastness assessment can support. Avoid it unless a separate, substantiated claim program defines exactly what it means.
What the recognized methods actually establish
AATCC TM162 is intended to evaluate the resistance of color in dyed, printed, or otherwise colored textile yarns and fabrics to chlorinated pool water. Its summary describes specimens agitated in a diluted chlorine solution under specified temperature, time, pH, and hardness conditions, then dried and evaluated for color change. It also identifies a chlorine test control fabric used to verify correct test performance. AATCC TM162
DIN’s overview of EN ISO 105-E03 describes three alternative conditions for active-chlorine exposure: 50 mg/l and 100 mg/l for swimwear, and 20 mg/l for accessories such as beach robes and towels. The specimen is treated and dried, then color change is assessed with a grey scale or instrumentally. DIN EN ISO 105-E03
The buyer takeaway is not to prescribe a home-made chlorine recipe. Instead, name the selected method and edition, specify the applicable condition in the test request, and have a qualified laboratory perform the method. A report without the condition used leaves an important approval gap, particularly when the product category could reasonably fit more than one exposure scenario.
For TM162 approval, keep the stated endpoint focused on color change of the tested specimen. Do not add an adjacent-fabric staining requirement to a TM162 request unless another separately selected method and product risk justify it. Combining endpoints from different methods can make a report difficult to interpret and harder to compare from one development round to the next.
Choose the method from product use, not garment category alone
“Swimwear” is useful merchandising language, but it may be too broad for technical approval. Start with the actual role of the item and its likely pool contact.
A fitted swimsuit, rash guard, board short, swim legging, or pool-training garment may warrant an ISO 105-E03 condition intended for swimwear. A beach robe, cover-up, towel, or poolside accessory may call for the accessory-oriented condition. The point is not that one group is inherently better than another; it is that the exposure condition should follow the use case you intend to approve.
The same style can need more than one material decision. Consider a color-blocked suit with a dark shell, pale binding, printed logo, mesh lining, and elastic trim. The buyer should decide which components are in scope, whether each must be submitted, and whether the visual approval standard applies to the component alone or to the assembled design. If only the navy shell is tested, do not extend that result to white binding or a metallic print without evidence.
Color selection deserves similar discipline. Deep, bright, fluorescent-looking, pastel, heathered, garment-dyed, washed, and heavily printed appearances can each create different approval risks. That does not mean any shade will fail; it means a buyer should identify the commercial colorways that need evidence rather than approving an entire palette by inference from one lab dip.
Build a decision framework that prevents ambiguous approvals
A workable buyer decision has five parts: scope, specimen identity, method choice, acceptance rule, and release consequence.
Scope: identify what customers will actually expose
Write a plain-language use statement before sending a test request. For example: “This approval concerns color change after chlorinated pool-water exposure for the shell fabric used in the named swim short colorways.” This sentence disciplines the rest of the process. It tells the team what is included and prevents a later claim that the approval covered lining, prints, or beach use when it did not.
Specimen identity: link the report to the production decision
A report is useful only when its specimen can be connected to the approved material. Record the supplier material reference, composition as declared in the development record, color name or code, dye lot or development lot where available, construction or finish identifier, and specimen stage. State whether the submission is a lab dip, fabric swatch, sample-yardage cutting, pre-production material, or bulk-lot sample.
A result from an early swatch can support material selection, but it is not automatically the same as bulk-release evidence. Buyers should decide in advance which stage carries final approval authority.
Method choice: lock the standard and selected condition
Specify the standard name, edition, and applicable condition before testing. Do not allow a generic phrase such as “test for chlorine resistance” to be the complete instruction. It does not tell the laboratory which method the buyer expects, nor does it give the commercial team a stable basis for comparing reports.
If a customer requirement, retailer manual, or market program names a different method, preserve that requirement exactly in the RFQ and purchase order. Where no external requirement exists, select the method that best matches the stated product use and document the commercial rationale.
Acceptance rule: set it before results arrive
There is no sensible universal grade to copy into every apparel program. A buyer’s minimum acceptable color-change result should reflect the product’s use, shade sensitivity, brand positioning, applicable customer requirement, and tolerance for visible variation. Define the rating approach and minimum result before a sample is submitted.
For visual products, add a practical review step: compare the post-test specimen with the approved reference under the brand’s normal color-evaluation process. A numerical or scale-based result can inform approval, but it does not replace a buyer’s responsibility to decide whether the appearance remains acceptable for that specific design.
Release consequence: say what happens when evidence is incomplete
A complete approval plan says whether a passing result releases bulk fabric, only releases sampling, or triggers another confirmation at pre-production or bulk stage. It should also state what happens if the report omits the condition, identifies the wrong colorway, uses an unapproved specimen, or reports a result below the agreed threshold. Ambiguity at this point often becomes a preventable production dispute.
A numbered approval workflow for apparel teams
- Write the customer-use statement. Identify whether the item is intended for swimming, poolside wear, or another exposure pattern. Keep the statement limited to the color-retention question.
- Map every visible color-bearing component. List shell fabric, contrast panels, prints, embroidery, bindings, linings, labels, and trims that could affect the customer’s visual impression. Decide which need individual evidence and which are outside the claim.
- Select the method and condition. Put the exact standard, edition, and selected exposure condition in the test request. Do not leave the lab to infer the commercial use case.
- Set the acceptance criteria before submission. Define the required color-change assessment, minimum result, reporting format, and the person authorized to approve exceptions.
- Submit identifiable material. Ensure the test specimen is traceable to the relevant colorway and development or production stage. Retain the approved reference swatch with the technical file.
- Review the report for completeness. Confirm the method, condition, specimen identity, assessment approach, result, and any stated deviations. A passing number without specimen traceability is not a clean approval.
- Compare evidence with the actual product claim. If the marketing team wants to say more than the test addresses, either narrow the language or establish a separate evidence plan.
- Release, hold, or retest with a documented reason. Record the decision against the same material reference used in sourcing and production communication. Carry the approved scope into reorder records.
RFQ questions that improve supplier and laboratory alignment
Use these questions in an RFQ, development brief, or test authorization:
- Which exact material references, colorways, print applications, and visible trims are included in this request?
- Is the requested evidence for sampling approval, pre-production approval, bulk release, or a customer submission?
- Which test method, edition, and exposure condition applies to this product use?
- Is the approval endpoint limited to color change of the specimen?
- What minimum result and assessment approach constitute acceptance?
- Must the report identify the sample stage and material/color reference?
- If the result is outside the acceptance rule, who decides whether to revise color, dye process, print application, or product claim?
- Does any retailer, distributor, or licensing agreement impose additional requirements that must appear in the purchase order?
These questions are also useful when working with an apparel development partner. JUNSHEEN can use a clear technical brief to coordinate material sourcing, sampling, and approval communication without turning a vague “chlorine resistant” request into an unsupported product promise.
Red flags buyers should resolve before bulk commitment
The most common red flag is a report described only as “chlorine tested.” Ask for the full method and condition rather than assuming the result suits your product. Another is a result tied to an unnamed swatch, which cannot be reliably connected to the colorway approved for production.
Be cautious when a supplier presents one result as proof for all colors, fabrics, prints, and trims in a collection. It may be relevant as development context, but it is not automatically component-by-component approval. The same caution applies when a passing pool-exposure color result is used to support claims about saltwater, laundering, UV exposure, elastic longevity, or waterproofness.
Compact buyer checklist
Before approving colorfastness to chlorinated pool water, confirm that the file contains:
- A defined pool-use scenario and a statement limited to color change.
- The exact test method, edition, and selected condition.
- Material, colorway, component, and specimen-stage identification.
- A pre-agreed acceptance threshold and assessment format.
- A report review for method, condition, specimen identity, result, and deviations.
- A written release decision tied to the appropriate sampling or production stage.
- Product copy that does not extend the evidence to seawater, laundry bleach, water resistance, or lifetime performance.
For shorts programs, the Custom Shorts Manufacturer page is a useful starting point for defining fabric, fit, print, trim, and sample requirements alongside the pool-exposure approval question.
Buyer FAQs
Is colorfastness to chlorinated pool water the same as chlorine-proof?
No. A colorfastness result addresses the reported color change under its specified exposure. “Chlorine-proof” is broader language and should not be used unless separately defined and supported.
Can one passing fabric report approve every colorway?
Not automatically. Approve only the materials, shades, components, and sample stages identified in the report or explicitly covered by your written approval scope.
Should a pool-water test replace seawater testing?
No. Pool exposure and seawater are different buyer scenarios. Request evidence that matches the exposure claim you plan to make.
Does this approval prove that prints and trims will perform the same way as the shell fabric?
No. Include print applications, contrast materials, embroidery, and trims in the plan when their color appearance matters to the product.
What should a buyer do when the report lacks a condition or material reference?
Treat it as incomplete for final approval. Request clarification or a correctly identified submission before releasing the claim or the relevant production stage.
Put the evidence into the product brief
The best pool-colorfastness approval is not a standalone lab document. It is a traceable decision that connects customer use, material selection, colorway scope, exposure condition, acceptance rule, report review, and accurate product language. When your apparel program needs this level of definition, discuss your project with the development brief, material references, intended use, and approval requirements.
Sources
- AATCC TM162 Test Method for Colorfastness to Water: Chlorinated Pool — Method scope, controlled exposure summary, color-change endpoint, and control-fabric reference.
- DIN EN ISO 105-E03:2010-08 — Chlorinated-water colorfastness scope, alternative conditions, intended product categories, and color-change assessment overview.
