How to Read a Knit Fabric Test Report: A Buyer's Guide

September 2, 2026

AI-assisted edit of an original FJORATEX fabric photograph; not a test result.

Read a knit fabric test report in this order: identify the sample, confirm the method and conditions, locate the acceptance requirement, interpret the actual result, and check whether the sample represents production. A PASS means little if the tested fabric, wash procedure or buyer specification differs from your order.

A report describes one sample under stated conditions. It is useful evidence for a purchasing decision, but it does not give the fabric permanent approval for every product, colour and production batch.

1. Does the report describe the fabric you are buying?

Start with the sample description, not the results page. Match the report to the current specification and approved sample:

Fabric reference, development revision and supplier reference.
Fibre composition, knit structure, weight in GSM and usable width.
Colour, finish and any functional treatment.
Sample or production batch, report number and issue date.

“Black polyester knit” is not enough to distinguish two development versions. If the report omits details, verify them against the submission form and supplier records. Do not assume a familiar fabric name proves a match.

Construction matters here. A single jersey and an interlock should not be treated as the same sample simply because their fibre percentages match. The same caution applies when a merino blend changes yarn, weight or finish during development.

2. Which method and conditions were used?

Request the full method designation, including year, relevant amendments and selected procedure. AATCC's designation guidance explains why the organisation, document type, number and year belong together.

For example, AATCC TM135-2025 measures fabric length and width changes after home laundering. A result still needs its washing, drying and cycle details. “Shrinkage: 2%” leaves too much unanswered.

ISO 6330:2021 provides domestic washing and drying procedures, not a universal shrinkage limit. Its public summary notes that machine, detergent and drying parameters can affect results. Flat-dried and tumble-dried samples therefore need separate context.

Also check test direction, units, prewashing and conditioning. ISO 139:2005, including Amendment 1:2011, addresses conditioning and test atmospheres. Lengthwise and widthwise results are not interchangeable; neither are percentages, pressure values, cycle counts and visual grades.

A newer edition does not automatically override the version named in a contract. If the report and buyer manual differ, resolve that mismatch with the laboratory before comparing results or ordering a retest.

3. What is the difference between method, requirement and result?

Keep these three fields separate:

Method: how the laboratory tested the sample.
Requirement: the acceptance criterion for this order.
Result: what the submitted sample actually achieved.

A test method is not, by itself, a product acceptance specification. Requirements may come from applicable regulation, a buyer manual, a contract or an agreed product specification.

Suppose a report says PASS for dimensional change. Ask which specification revision supplied the limit, which directions it covers and which laundering procedure applies. Without those details, another brand's PASS cannot become your approval.

Keep measured results even when a pass/fail decision is supplied. Actual values help you compare development rounds and see how close a result sits to the agreed limit. A tick box cannot do either job.

4. What do the main knit fabric tests tell you?

Use the product's likely failure modes to read the test list. Similar-sounding tests can answer different questions.

Test area	Example method	What the result addresses
Dimensional change	AATCC TM135-2025	Length and width changes after specified laundering
Pilling	ISO 12945-2:2020	Pilling, fuzzing and matting under the modified Martindale method
Abrasion	ISO 12947-2:2016	Specimen breakdown under Martindale abrasion
Rubbing colourfastness	AATCC TM8-2016e(2022)e	Colour transfer through dry or wet rubbing
Bursting strength	ISO 13938-2:2019	Resistance to pneumatic pressure and associated expansion
Spirality after washing	ISO 16322-2:2021	Fabric twisting after laundering, using a specified procedure

Pilling, abrasion and rubbing colourfastness are not substitutes. A fabric can retain its structure while developing pills or transferring colour. Likewise, a bursting result does not establish seam strength or stretch recovery.

Compare results only when the method and relevant conditions match. ISO 16322-2 explicitly warns that results from its different procedures are not always comparable. A lone “torque” number is therefore not enough.

5. Can a development report represent bulk production?

First identify what was tested: an early sample, an approved sample, a trial dye lot or a production batch. These are different evidence points.

Then check what has changed. Fibre blend, yarn, construction, GSM, colour, finishing and production route are useful prompts for a review. A report on an unfinished development sample does not automatically validate the finished order.

A practical approach is to ask which properties each change could affect, then agree targeted verification. This does not mean repeating every test after every minor adjustment. Sampling and retesting should reflect the product risk and the buyer's requirements.

Which tests deserve the budget first?

The following is a discussion framework, not a standard-mandated package or a fixed FJORATEX policy:

Non-negotiable requirements: applicable market, customer and contractual obligations.
Likely product failures: risks such as unacceptable wash change, colour transfer or structural damage.
Claim evidence: tests supporting the specific performance statements the brand intends to use.
Exploratory work: comparisons that help development but are not yet acceptance requirements.

A small order does not remove required testing. A large order does not justify every available test. Early screening can narrow candidates; formal verification can follow at agreed approval points.

Before sending samples, agree who pays for initial testing, sample consumption, shipping, investigation and retesting. Also define what happens when the specification changes. These arrangements need project-specific agreement, not assumptions about industry custom.

What should you check about the laboratory?

ISO/IEC 17025:2017 addresses laboratory competence, impartiality and consistent operation. Accreditation still has a defined scope. ILAC advises checking status and scope with the relevant accreditation body; a logo alone does not confirm coverage of every test.

Factory screening and independent testing can serve different purposes. Specify whether the data is for development comparison, buyer approval or another requirement before deciding what evidence is sufficient.

Frequently asked questions

What is an acceptable shrinkage percentage for knit fabric?

There is no single acceptance limit for every knit. Use the requirement agreed for the product, direction, laundering procedure and cycle count. A percentage without those conditions is not a complete specification.

Does a PASS mean the fabric is ready for production?

Not automatically. Confirm the sample identity, applicable requirement and whether the tested version matches the production plan. A development result cannot guarantee all future batches.

Must every colour be tested?

The answer depends on buyer requirements and the risks being assessed. Agree a colour and sampling plan with the supplier and laboratory; do not assume one colour covers all dyeing and finishing combinations.

Turn the report into a clear development brief

FJORATEX is a knit fabric development and sourcing partner. For a project discussion, bring the end use, current specification, intended care instructions and available reports. Contact FJORATEX to discuss priorities; test scope, acceptance criteria and costs must be agreed for each project.

For application-specific reading: merino wool blend testing and running and training shirt testing.

Sources

Public summaries support the method descriptions below. They do not replace full standards or the buyer's specification. Sources checked on 2 September 2026.

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