Views: 0 Author: Site Editor Publish Time: 2026-06-23 Origin: Site
Based on the national standards GB/T 28004.2-2021 Paper diapers – Part 2: Adult diapers and GB 15979-2024 Hygienic requirements for disposable sanitary products, this article compiles a practical sample testing protocol that purchasers can operate independently and that yields quantifiable data. It covers six core test methods: absorption rate, rewet value, tensile strength, saturated absorption capacity, leakage prevention, and hygiene/safety. All test values specified are the actual standard values from the national standards, and purchasers can directly use this protocol to verify samples from any manufacturer. The following is a sample testing method based on national standards that helps you quickly assess a supplier's true capability. It is organized into three steps: “Check, Test, and Ask”.
Before starting hands on testing, do these two things:
1. Request and verify qualification documents
Ask the supplier for third-party test reports and confirm that the products comply with GB/T 28004.2-2021 Paper diapers – Part 2: Adult diapers.
Check whether the hygiene standard GB 15979 2024 Hygienic requirements for disposable sanitary products is followed.
Verify that the outer packaging clearly displays the product name, standard number, production date, main raw materials, manufacturer name and address, etc.
2. Sensory inspection of samples
Open the package and smell for any irritating odour.
Check whether the surface is flat, without damage, foreign matter, powder shedding, or fibre shedding.
Feel the surface material with your hand – thermal bonded nonwoven is softer and more skin friendly than ordinary nonwoven, and is a hallmark of a high quality product.
Step 2: Test – Core Performance Tests (Focus Area)
The test methods below are based on GB/T 28004.2 2021. It is recommended to ask the supplier for at least 3 5 samples for parallel testing and take the average value.
Purpose: The absorption rate determines how quickly urine is locked away. The slower the rate, the longer the liquid stays in contact with the skin, increasing the risk of skin irritation.
Method:
Prepare a 0.9% NaCl saline solution and heat it to 36±1 °C (to simulate body temperature).
Lay the adult diaper flat and place a 2.0±0.2 kPa weight on it to simulate body pressure.
Pour the test solution from directly above, and time with a stopwatch how long it takes for the liquid to be completely absorbed.
Evaluation criteria:
First absorption rate ≤ 50 s (pass)
Second absorption rate ≤ 100 s (pass)
The lower the value, the better the performance.
⚠️ Note: If the supplier is unwilling to perform even this basic test, or if the test results significantly exceed the standard, it indicates that the absorbent core quality is substandard.
Purpose: The rewet value reflects the “dryness” of the adult diaper – i.e., whether liquid returns to the surface after being absorbed. The lower the rewet value, the drier the skin remains.
Method:
After completing the absorption rate test (and after the second addition, let it stand for 15 minutes).
Place 15 layers of pre weighed absorbent filter paper on the adult diaper surface.
Apply a 4.0±0.2 kPa weight for 1 minute.
Remove the filter paper and weigh it again; the weight increase of the filter paper equals the rewet value.
Evaluation criteria:
Moderate incontinence products: rewet value ≤ 30.0 g
Severe incontinence products: rewet value ≤ 40.0 g
The lower the value, the better the dryness.
�� Additional tip: The Sichuan Provincial Administration for Market Regulation, in its consumer advisory, recommends choosing products with a high content of superabsorbent polymer (SAP) and low rewet values. You can cut open a used sample to examine the core – products with a high SAP content will show a transparent gel like state after absorption, rather than a wet, cotton wool like appearance.
Purpose: Tensile strength determines whether the underpad is prone to tearing or breakage during use.
Simple test method:
Take one underpad and cut a 100 mm × 50 mm rectangular specimen along both the longitudinal and transverse directions.
Hold each end with both hands and pull evenly in opposite directions, feeling the force required to tear the material.
Observe whether the tear occurs in the material itself or at the seam – the latter often indicates a manufacturing defect.
Evaluation criteria:
National standard requirement: longitudinal tensile strength ≥ 10 N
High quality products: longitudinal/transverse tensile strength ≥ 40 N
The higher the value, the more durable the product.
�� Professional advice: If conditions permit, you can commission a third party testing laboratory to perform accurate tests using a tensile testing machine. Samples should be conditioned in a constant temperature and humidity environment (23±2 °C, 50±5% RH) for 24 hours before testing.
Purpose: Indicates the maximum amount of liquid one underpad can absorb.
Simple test method:
Take one underpad and weigh it to record its initial weight (W1) .
Completely immerse it in 0.9% NaCl saline solution for 30 minutes.
Remove and hang to drip drain for 10 minutes, then weigh again to obtain the absorbed weight (W2) .
Absorption ratio = (W2 – W1) / W1
Evaluation criteria:
Moderate incontinence diapers: saturated absorption capacity ≥ 300 g
Severe incontinence diapers: saturated absorption capacity ≥ 600 g
Underpads (pads): no leakage or seeping through
Step 3: Ask – Enquire About the Supplier’s Quality Control System
After passing the sample tests, a few more questions can help you further judge the supplier’s capability:
1. Ask about raw material sources
Which brand of superabsorbent polymer (SAP) do they use? Where does the fluff pulp come from?
High quality SAP suppliers (e.g., Nippon Shokubai, BASF, etc.) offer much better product consistency than small local producers.
2. Ask about factory release tests
Are permeability properties (absorption rate, rewet, and leakage) tested on every batch?
Is pH value tested (standard requires 4.0-8.5)?
Are formaldehyde content (standard requires ≤75 mg/kg) and migratory fluorescent substances (must not be detectable) tested?
3. Ask about third party testing frequency
How often do they send products for third party testing?
Can they provide third party test reports from the last six months?
Summary: A Sample Test Record Template
We recommend recording your test results in a table like the one below, so you can easily compare different suppliers:
Test Item | National Standard Requirement | Sample Result | Verdict |
First absorption rate | ≤50 s | ___ s | ☐ Pass ☐ Fail |
Second absorption rate | ≤100 s | ___ s | ☐ Pass ☐ Fail |
Rewet value | ≤30 g (moderate) / ≤40 g (severe) | ___ g | ☐ Pass ☐ Fail |
Longitudinal tensile strength | ≥10 N | ___ N | ☐ Pass ☐ Fail |
pH value | 4.0-8.5 | ___ | ☐ Pass ☐ Fail |
Formaldehyde content | ≤75 mg/kg | ___ mg/kg | ☐ Pass ☐ Fail |
Migratory fluorescent substances | Not detectable | ☐ Not detected ☐ Detected | ☐ Pass ☐ Fail |
If you are a nursing home procurement officer, a chain pharmacy purchaser, a domestic distributor, or a cross-border independent site merchant, and you are currently comparing multiple adult underpad suppliers, please contact Jiangsu Noda Hygiene Products Co., Ltd. to request free sample kits of various specifications, each accompanied by a complete factory inspection report.
We support customers in independently verifying our products against all the test methods described above, and we also welcome appointments for on site visits to our automated production lines. Our offerings include regular stock for mixed-batch orders, full container exports, and private label OEM services. We provide a one stop solution that addresses the common procurement pain points of inconsistent quality in bulk purchases, high post sale loss rates, and high barriers to customization.
