AATCC TM22 Spray Test Explained: Water-Repellent Fabric Buyer’s Guide

AATCC TM22 is one of the most frequently requested test methods for water-repellent outdoor, apparel and technical fabrics. It evaluates how effectively a textile surface resists wetting when exposed to a controlled water spray.

The test is especially useful for comparing durable water-repellent finishes, commonly called DWR finishes. However, a high spray rating does not prove that water cannot penetrate the fabric, and it does not automatically make a garment, tent, bag or cover waterproof.

What Is AATCC TM22?

AATCC TM22-2024 is titled Test Method for Water Repellency: Spray Test. It can be applied to textile fabrics with or without a water-repellent finish.

During the test, water is sprayed onto a fabric specimen held at a defined angle under controlled conditions. The resulting surface-wetting pattern is visually compared with the official AATCC photographic evaluation scale.

The result indicates the relative ability of the fabric surface to resist wetting. It is particularly useful for checking the initial performance and durability of a DWR treatment.

What Does the AATCC TM22 Spray Rating Mean?

AATCC TM22 results are commonly reported on a numerical scale from 0 to 100. Higher ratings indicate less visible wetting of the tested surface, while lower ratings indicate more extensive wetting.

Accuracy note: Laboratories should assign the official rating by comparing the specimen with the current AATCC photographic scale. The descriptions above provide general buyer guidance and do not replace the copyrighted standard or official evaluation chart.

Water Repellent and Waterproof Are Not the Same

The distinction between water repellency and waterproofness is essential when preparing a fabric inquiry.

A lightweight woven fabric can receive an excellent initial spray rating while still allowing water to penetrate through its construction under pressure. Conversely, a coated fabric may resist water penetration even when its outer surface begins to wet.

For rainwear and outdoor equipment, buyers may need both surface-repellency and water-penetration data.

AATCC TM22 Compared with Other Water Tests

Accuracy note: Test selection depends on the product standard, construction, exposure and buyer requirement. These methods evaluate different water-related properties and their results should not be treated as interchangeable.

What Affects a Fabric’s Spray Rating?

1. DWR Chemistry and Application

The type of water-repellent chemistry, application level, drying and curing conditions can all affect the result. The finish must be compatible with the fiber, dyes, coatings and other functional treatments used on the fabric.

PFC-free and other fluorine-free DWR systems can be developed for strong water repellency, but their behavior should be verified on the actual production construction. Performance cannot be guaranteed from the chemistry name alone.

2. Fiber and Yarn Construction

Polyester, nylon, cotton and blended fabrics interact differently with water and finishing chemicals. Yarn shape, filament count, twist and texturing can also influence how evenly the finish is applied and how the surface wets.

3. Fabric Density and Surface Texture

Tightly woven taffeta, ripstop, Oxford and Taslan fabrics may display different water-beading patterns. Brushed, raised, wrinkled or heavily textured surfaces can also make visual assessment more difficult.

4. Dyeing, Printing and Other Finishes

Dyes, pigments, print binders, softeners, antistatic agents, wicking finishes and coating auxiliaries may interact with the DWR treatment. Testing an untreated laboratory sample does not qualify the final dyed, printed or coated fabric.

5. Contamination and Handling

Detergent residue, oil, dust and repeated handling can reduce surface repellency. Samples should be conditioned, stored and handled consistently before evaluation.

Why Buyers Should Test After Laundering

An initial spray rating shows how the new fabric performs, but many products require water repellency after repeated care or use.

Outdoor jackets, workwear, uniforms and washable accessories may experience detergent exposure, abrasion, heat and repeated flexing. These factors can reduce the effectiveness of the surface treatment.

A complete specification should therefore identify:

• The required initial spray rating.
• The number and type of laundering or cleaning cycles.
• The detergent, water temperature and drying procedure.
• Whether heat reactivation or another aftercare treatment is allowed.
• The required spray rating after conditioning.

Recommended Applications

Outdoor Jackets and Pants

AATCC TM22 is useful for evaluating whether light rain or splashes bead on the outer fabric. Buyers should also assess breathability, moisture-vapor transmission, hydrostatic pressure, seam construction and performance after laundering.

Tents, Awnings and Outdoor Covers

Surface repellency can help reduce wetting and water absorption, but tent and cover fabrics may also require hydrostatic-pressure, rain, coating-adhesion, UV-weathering and seam-leakage tests.

Backpacks and Equipment Bags

A water-repellent outer surface can provide useful protection against brief exposure. However, coatings, laminations, seams and zippers normally determine whether the complete bag can resist water penetration.

Workwear and Uniforms

Workwear may require repellency against rain or water-based splashes. If chemicals, oils or hazardous liquids are involved, AATCC TM22 alone is not sufficient; application-specific protective-clothing requirements may apply.

Umbrellas and Canopies

Spray testing may support surface-finish evaluation, but prolonged rain exposure, leakage, UV stability, colorfastness and mechanical strength should also be included in product development.

How to Specify AATCC TM22 in a Fabric Inquiry

Instead of writing only “waterproof fabric” or “AATCC 22 passed,” provide the supplier with a measurable specification:

• Test method: AATCC TM22-2024.
• Target result: the required spray rating.
• Test stage: laboratory sample, approved quality or bulk production.
• Fabric condition: initial and after a defined care or exposure procedure.
• Construction: fiber, yarn, weave or knit, weight and width.
• Color and finish: final production colorway, print, coating and DWR system.
• End use: jacket, pants, bag, tent, cover, umbrella or another application.
• Additional tests: hydrostatic pressure, rain, impact penetration, breathability or seam performance as required.

Common Buyer Mistakes

• Using “water repellent” and “waterproof” as interchangeable terms.
• Assuming a high spray rating proves resistance to water penetration.
• Accepting “AATCC 22 passed” without a reported numerical result.
• Failing to identify the edition of the test method.
• Testing only the new fabric when durability after washing is required.
• Using a result from one color or finish to approve every production version.
• Ignoring seams, zippers and assembly construction in the final product.
• Assuming all PFC-free DWR systems provide identical performance.

Frequently Asked Questions

Does AATCC TM22 prove that a fabric is waterproof?

No. It evaluates resistance to surface wetting. It does not measure the pressure required to force water through the fabric and does not evaluate leakage through a complete garment or product.

What is the current version of AATCC TM22?

The current published edition is AATCC TM22-2024. Buyers should confirm the required edition with the laboratory and applicable product specification.

Is a rating of 100 required for every product?

No. AATCC TM22 is a test method rather than a universal product specification. The buyer, brand or applicable performance standard must define the appropriate initial and post-care acceptance levels.

Can a fabric have a high spray rating but low hydrostatic pressure?

Yes. Surface water repellency and resistance to water penetration are different properties. A fabric may bead water effectively but still allow penetration under pressure.

Should every color be tested?

Color and finishing chemistry can influence performance. The testing plan should cover representative or risk-sensitive colorways, and buyers should not automatically assume that one result applies to every production color.

Does PFC-free DWR pass AATCC TM22?

PFC-free DWR systems can achieve useful spray-test performance, but the result depends on the chemistry, fabric construction, application, curing and care conditions. The finished production-representative fabric must be tested.

Final Recommendation

AATCC TM22 is an effective quality-control tool for evaluating and comparing the surface water repellency of textile fabrics. Its value depends on a clearly defined target, consistent specimen preparation and testing in conditions that represent the intended product.

For a complete sourcing decision, combine the spray rating with the appropriate water-penetration, durability, breathability and finished-product tests. Always distinguish a water-repellent surface from a genuinely waterproof fabric or assembly.

Technical reference: AATCC TM22-2024, Test Method for Water Repellency: Spray Test. This buyer guide summarizes sourcing considerations and does not reproduce or replace the official standard.