Fabric Test Reports Explained: GB/T vs ISO, AATCC and ASTM, Test by Test
Mibein
Updated November 12, 2026
Testing & StandardsBuyer’s Guide
Our fabric test reports are issued to Chinese national (GB/T) and industry (FZ/T) methods. Most brand specifications are written to ISO, AATCC or ASTM. This guide puts the two side by side, test by test, so you can see in minutes which numbers to check, how they compare, and where they cannot be compared.
Mibein Textile Team · Guangzhou, China · Updated November 2026
Key Takeaways
Most Chinese colour-fastness methods are modified adoptions of ISO 105 parts. Grades on the same 1–5 grey scale can be read side by side with ISO results.
Some tests have no direct international twin: circular-locus pilling, charge-density antistatic, clo by plate method, Q-max and far-infrared. Compare those only against the same method.
Air permeability in mm/s (GB/T, ISO) and in cfm (ASTM D737) use different test pressures and areas. Converting the unit does not make the results equal.
In two places the Chinese rule is stricter than common practice elsewhere: moisture-wicking claims must hold after washing, and a “UV-protective” claim needs UPF above 40 with UVA transmission below 5%.
Every result applies only to the sample, colour, lot and conditions on the report. Always check those four lines first.
Start here: which numbers matter for your product
Most sourcing decisions depend on three or four tests. Check these first, then read the rest of the report for completeness.
If you are developing…
Check first
Why it decides the order
Training tees, running, gym wear
Moisture management (GB/T 21655.2 or AATCC TM195), pilling, colour fastness to perspiration
Sweat handling and surface wear are what customers notice in the first month
Golf polos, outdoor and sun-exposed tops
UPF and UVA transmission, colour fastness to light, snagging
Sun exposure drives both the claim and the most common return reason, fading
Base layers, fleece, cold-weather mid-layers
Thermal insulation (clo), pilling, antistatic
Warmth is the purchase reason; fleece pills and holds static if the yarn and finish are wrong
Lifestyle, polo and smart-casual knits
Pilling, colour fastness to washing and rubbing, dimensional change
These garments are washed often and judged on looking new
Mandatory for market access, not optional performance
How Chinese standards relate to international ones
The foreword of a Chinese standard states its relationship to the international original:
IDT (identical): technically the same as the ISO text.
MOD (modified): based on the ISO method with stated changes, usually local reference materials or minor procedural details. Results are generally comparable when the same options are chosen.
No equivalent: a Chinese method with no direct ISO or AATCC counterpart. Treat the result as information about the fabric, not as a substitute for the method your brand specifies.
Test by test: our methods and their international counterparts
These are the methods that appear in our third-party reports, grouped by property. Where a limit is quoted, it is the level printed on our reports or set by the Chinese standard; your own specification may differ.
Moisture management and quick-dry
Method on our reports
International counterpart
Same or different
How to read the result
GB/T 21655.2-2019, dynamic moisture transfer
AATCC TM195
Same instrument principle and a similar 1–5 grading scale; grade limits are close but not guaranteed identical, so compare raw values. GB/T adds a labelling rule: wetting time, absorption speed, bottom-surface wetted radius and spreading speed all at Grade 3 or better, before and after washing
No single equivalent; closest are AATCC TM79 (drop absorbency), TM197 (vertical wicking), TM201 (drying rate)
Different: one combined grade instead of separate tests
Grade I, II or III (III best), set by the weakest of water absorption, drip diffusion, wicking height and drying rate
Surface durability: pilling, snagging, abrasion
Method on our reports
International counterpart
Same or different
How to read the result
GB/T 4802.1-2008, circular locus pilling
No ISO equivalent. US specs often use ASTM D3512 (random tumble, equivalent in principle to GB/T 4802.4) or ASTM D4970
Different method. Grades are not interchangeable
Grade 1–5, 5 = no pilling. Always note cycles and load, e.g. “50 cycles, 490 cN”; a 600-cycle, 780 cN result is a different test
GB/T 4802.2-2008, modified Martindale pilling
ISO 12945-2 (MOD), ASTM D4970
Same principle
Grade 1–5 at a stated number of rubs
GB/T 11047-2008, mace snagging
ASTM D3939 (mace); ISO 25086-1:2026
Same principle
Grade 1–5, reported for length and width directions; read the lower one
Colour fastness
Method on our reports
International counterpart
Same or different
How to read the result
GB/T 3921-2008, washing
ISO 105-C10:2006 (MOD); AATCC 61 is a different, accelerated method
ISO-aligned. Do not compare with AATCC 61 results directly
Two grey-scale grades, 1–5: colour change of the fabric, and staining on each fibre of the multifibre strip. Read the lowest staining grade
GB/T 3920-2008, rubbing
ISO 105-X12 (MOD); AATCC 8
Same principle
Dry and wet grades 1–5. Wet rubbing is the weak point for dark shades
GB/T 3922-2013, perspiration
ISO 105-E04:2013 (MOD); AATCC 15 uses acid perspiration only
ISO-aligned; GB/T reports acid and alkaline
Change and staining grades for both solutions
GB/T 5713-2013, water
ISO 105-E01
ISO-aligned
Change and staining grades 1–5
GB/T 8427-2019, light (xenon arc)
ISO 105-B02:2014 (MOD); AATCC TM16.3 reports by AATCC fading units (AFU)
ISO-aligned. AATCC results in AFU hours are not the same scale
Blue-wool grade 1–8 (8 best). Note the method number and the blue-wool set used
GB/T 29778-2013, phenolic yellowing
ISO 105-X18
Same principle
Grade 1–5; relevant for white and pale shades stored in plastic packaging
Comfort and function
Method on our reports
International counterpart
Same or different
How to read the result
GB/T 18830-2009, UV protection
EN 13758-1/-2; AS/NZS 4399; AATCC TM183 with ASTM D6603
The claim rule matches EN 13758-2: UPF above 40 and UVA transmission below 5%. Australian and US labelling start from UPF 15, and US practice adds pre-conditioning (ASTM D6544) before labelling
Look for both numbers: the UPF value and T(UVA) %. A high UPF with UVA above 5% does not meet the Chinese or EU claim rule
GB/T 5453-1997, air permeability
ISO 9237 (MOD); ASTM D737
GB/T and ISO use 100 Pa over 20 cm² for apparel. ASTM D737 uses 125 Pa over 38.3 cm²
mm/s, higher is more breathable. Converting mm/s to cfm (1 ft³/min/ft² ≈ 5.08 mm/s) changes the unit only; the different pressure still makes results non-identical
GB/T 12703.1-2021 (half-life) and GB/T 12703.2-2021 (charge density), antistatic
No direct equivalent; international specs often use surface resistivity (EN 1149-1, AATCC TM76)
Different principles. Not comparable
Half-life in seconds (lower is better); charge density in μC/m², with a limit stated on the report
GB/T 35762-2017, thermal insulation
ISO 11092 / ASTM F1868 (sweating guarded hotplate, Rct)
Different apparatus. Not interchangeable
clo, higher is warmer. 1 clo = 0.155 m²·K/W
GB/T 35263-2017, contact cooling (Q-max)
No ISO or AATCC equivalent
Compare only with Q-max results
W/cm²; higher feels cooler on first touch
GB/T 30127-2013, far-infrared
No ISO or AATCC equivalent
Chinese method
Emissivity (limit ≥0.88 on our reports) and temperature rise (limit ≥1.4 °C)
GB/T 20944.3-2008, antibacterial (shake flask)
ASTM E2149 (shake flask). AATCC TM100 and ISO 20743 are absorption methods, closer to GB/T 20944.2
Same family as ASTM E2149; not the same as AATCC 100
% reduction for each named organism; check the wash count before testing
Test methods correspond to ISO 14184-1, ISO 3071 and EN ISO 14362-1
Methods are aligned; GB 18401 adds limits by product category
See the limits table below. “Not detected” means below the method’s detection limit, stated on the report
FZ/T 01057 series and GB/T 2910 series, fibre identification and content
ISO 1833 series
Aligned in principle
% by fibre; compare with the label composition and tolerance
GB/T 8629-2017, washing procedure used before tests
ISO 6330 (MOD)
Aligned
“4N” means programme 4N, a normal 40 °C wash. Check the number of cycles
GB 18401-2010 limits
Item
Category A (infants)
Category B (skin contact)
Category C (no skin contact)
Formaldehyde, mg/kg
≤20
≤75
≤300
pH
4.0–7.5
4.0–8.5
4.0–9.0
Colour fastness to water, grade
≥3-4
≥3
≥3
Colour fastness to acid and alkaline perspiration, grade
≥3-4
≥3
≥3
Colour fastness to dry rubbing, grade
≥4
≥3
≥3
Decomposable carcinogenic aromatic amines
Prohibited (limit 20 mg/kg)
Where each system asks more
The Chinese rule asks more on
Moisture-wicking claims: GB/T 21655.2 requires Grade 3 or better on four indices both before and after washing. AATCC TM195 classifies the fabric and leaves the pass mark to the buyer.
“UV-protective” claims: GB/T 18830 requires UPF above 40 and UVA transmission below 5%, the same rule as EN 13758-2, while Australian and US labels start from UPF 15.
Baseline safety: GB 18401 applies to all apparel sold in China, with formaldehyde, pH and colour-fastness limits by product category.
International practice asks more on
UV durability: US labelling practice pre-conditions fabric (ASTM D6544, simulated laundering and light) before measuring UPF.
Overall moisture score: AATCC TM195 still reports OMMC, which GB/T 21655.2-2019 removed.
Brand-specific methods: many brands specify ASTM D3512 pilling or AATCC 61 accelerated washing. If yours does, a GB/T report is useful evidence but not a replacement.
How to read any test report in six checks
Method and edition. “GB/T 3921-2008” and “AATCC 61-2013” are different tests even when both say “washing.”
Sample identity. Quality code, colour and lot. A report on navy does not cover white.
Condition. As received, after 5 washes, after 10 washes. The wash programme should be named.
Requirement column. Compare the result with the requirement printed beside it, not with a number from a different method.
Verdict type. Some reports print “Pass/符合”; others give values only. “Value only” is not a failure, it means no limit was applied.
Lab. Check the issuing laboratory and its accreditation marks (CNAS, CMA, ILAC-MRA) on the cover page.
Our results, read the way we recommend
Selected results from third-party reports on fabrics in our range. Each result covers the tested sample, colour and lot only.
Why colour matters: on one of our clone-cotton qualities, an early lot in a pale shade tested at UPF 46 with UVA transmission of 6.44% and failed the claim rule. A later lot in the same shade reached UPF 166, and black reached UPF 191. UV results belong to the lot and shade tested; ask for the report on your production colour.
Pilling, GB/T 4802.1-2008, 50 cycles at 490 cN (GTTC)
Share the methods and minimum grades your brand uses. We will match them against the reports we hold, show you where a GB/T result covers your requirement, and tell you plainly where a separate test would be needed.
