Most brands claim “premium fabric.” Very few back it with independent lab data. At LURI, every production lot goes through third-party testing across colour fastness, dimensional stability, spirality, and fabric weight — the four properties that determine whether a tee actually holds up or quietly degrades after a few washes.
“A grade of 4–5 on colour fastness. Spirality near zero. GSM at 260 g/m². Not marketing language — lab numbers.”
Who tests LURI fabric
LURI works with two independent, accredited textile testing laboratories. Neither is affiliated with LURI — their job is to test without bias and report exactly what they find.
SITRA — South India Textile Research Association
SPR Consumer Products Services
The numbers, plainly
4–5
~0°
260
ISO
What Do the Lab Tests Measure?
Colour Fastness — Does the colour stay?
Colour fastness testing measures how well a fabric holds its dye under real-world conditions. LURI fabrics are tested across five categories:
Rubbing (dry and wet): Our fabrics score 4–5 out of 5 on the rubbing test, meaning there is minimal to no visible colour transfer when the garment rubs against skin, furniture, or other fabrics. This test uses the ISO 105-X12 standard.
Washing: After domestic washing cycles tested under ISO 105-C10 and ISO 105-C06, LURI fabrics maintain a colour grade of 4–5, with very low staining on adjacent fibres. Your colours stay rich and consistent wash after wash.
Light exposure: Tested under ISO 105-B02, fabrics rate 4–5 for resistance to fading caused by sunlight and UV exposure — important for everyday outdoor wear.
Perspiration and water: Rated 4–5 under ISO 105-E01 and ISO 105-E04, meaning garments resist discolouration from sweat and water contact — two of the most common causes of premature fading in everyday T-shirts.
Shrinkage & Spirality — Does the fit hold?
Shrinkage testing under ISO 6330 measures how much a garment’s length and width change after washing. LURI fabrics consistently fall well within acceptable textile tolerances, so a garment that fits you on day one will continue to fit correctly after regular washing.
Spirality — the tendency of a garment to twist around the body after washing — is measured under ISO 16322-2. LURI fabrics show spirality values close to zero, meaning the side seams, neckline, and hem remain straight and aligned. This is especially significant for interlock knit constructions, which can be prone to twisting if fabric quality is not tightly controlled.
Fabric Weight (GSM) — Does it feel premium?
GSM stands for grams per square metre and is the standard measure of fabric density. Tested under ISO 3801, LURI’s Supima knit fabric measures approximately 260 g/m². This places it in the heavyweight premium category — substantial enough to feel structured and opaque, yet breathable enough for all-day comfort. Lightweight or low-GSM fabrics tend to feel thin and see-through; our 260 GSM construction does not.
What the Results Mean for You, in Plain Language
Your T-shirt will not fade. High colour fastness grades across washing, rubbing, light, perspiration, and water mean the colour you see in the product stays the colour you wear — even after 30, 40, or 50 washes.
Your T-shirt will not shrink out of shape. Controlled shrinkage within industry tolerances ensures that a Medium stays a Medium and an XL stays an XL after every wash cycle.
Your T-shirt will not twist. Near-zero spirality means the seams stay where they are supposed to — straight down your sides — not wrapped around to the front or back after washing.
Your T-shirt will feel premium. At 260 GSM with a soft-hand finish, LURI fabric has the drape and structure of a quality garment. It does not cling, go transparent, or feel flimsy.
Testing Standards Used
All LURI fabric tests are conducted under recognized international standards:
ISO 105-X12 covers colour fastness to rubbing. ISO 105-C10 and ISO 105-C06 cover colour fastness to domestic and commercial washing. ISO 105-B02 covers colour fastness to light. ISO 105-E01 and ISO 105-E04 cover colour fastness to water and perspiration. ISO 6330 covers dimensional stability after domestic washing. ISO 16322-2 covers spirality after washing. ISO 3801 covers fabric weight (GSM).
These are the same international standards used by global apparel brands and regulatory bodies.
Official Certification Reference
LURI fabrics have been tested and certified by SITRA (Report Nos. N2506284 & K2502416) and SPR Consumer Products Services (Report No. SPRTR25-262019) for colour fastness, shrinkage, spirality, and fabric weight (GSM).
The full lab report documents are available below for your review.
Frequently Asked Questions About LURI Fabric Quality
Yes. LURI partners with two independent, accredited laboratories — SITRA (NABL-accredited) and SPR Consumer Products Services, Tiruppur — for all fabric quality testing. We do not rely solely on manufacturer-provided data.
LURI uses Supima cotton, a premium long-staple cotton variety known for exceptional softness, strength, and colour retention compared to standard cotton.
Lab test results show colour fastness grades of 4–5 out of 5 across washing, rubbing, light, perspiration, and water tests — indicating that LURI fabrics are highly resistant to fading under normal use and washing conditions.
Shrinkage tests under ISO 6330 show that LURI fabrics shrink within acceptable textile industry tolerances. The garment will retain its size and fit with normal washing.
GSM measures fabric weight per square metre. At 260 GSM, LURI T-shirts are in the heavyweight premium category — thick enough to feel substantial and opaque, but still comfortable for everyday wear.
The official lab report documents from SITRA and SPR are uploaded on this page for full transparency.
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From – THE SOUTH INDIA TEXTILE RESEARCH ASSOCIATION
