Carpet Material Testing

Carpet material testing mainly conducts scientific testing and analysis on flame retardancy testing, physical and mechanical property testing, hazardous substance limit testing, colour fastness testing, electrostatic property testing and antibacterial and anti-mold performance testing, objectively assessing the product quality grade and issuing a detailed test report, providing a basis for manufacturers' quality control and downstream users' product acceptance.

Testing Items

Flame retardancy testing: This item aims to evaluate the ability of the carpet material to resist and suppress flames. Mainly in accordance with the relevant standards, simulating the conditions of fire source contact or radiant heat, parameters such as the afterflame time, afterglow time, damaged length and critical heat flux are measured. For public places and high-rise buildings, this item is a key content of mandatory safety testing.

Physical and mechanical property testing: This test comprehensively evaluates the durability and service performance of the carpet, including abrasion resistance, fatigue resistance, thickness change, peeling strength, tuft withdrawal force (tuft anchorage) and dimensional stability. These indicators directly affect the expected service life, appearance retention ability and laying effect of the carpet.

Hazardous substance limit testing: This test targets chemical substances that may be contained in carpet materials and are harmful to human health and the environment. The key test items include formaldehyde emission, total volatile organic compounds (TVOC), extractable heavy metals (such as lead, cadmium, chromium and mercury), styrene, 4-phenylcyclohexene (4-PC) and some banned azo dyes.

Colour fastness testing: This test evaluates the stability of the carpet colour under the action of external factors. Conventional test items include light fastness, rubbing fastness (dry and wet rubbing), water spot fastness and detergent fastness. Excellent colour fastness is an important premise for ensuring that the carpet can maintain a beautiful appearance after long-term use and cleaning.

Electrostatic property testing: Mainly evaluates the ability of the carpet material to generate and accumulate static charges due to friction in a dry environment. Its antistatic performance is determined by measuring its surface resistance or the half-life of the electrostatic voltage. This item is especially important for antistatic sensitive areas such as electronic equipment rooms and hospital operating rooms.

Antibacterial and anti-mold performance testing: This test evaluates the ability of the carpet to inhibit or prevent the growth and reproduction of microorganisms such as bacteria and mold on its surface. By inoculating specific strains (such as Staphylococcus aureus, Escherichia coli and Aspergillus niger), after culturing under specified conditions, the antibacterial rate or anti-mold grade is calculated, to evaluate its hygienic safety performance.

Testing Scope

Woven carpets: Refers to carpets produced by the interweaving process of warp and weft yarns, including Wilton woven carpets and Axminster woven carpets. Their testing needs to pay special attention to the stability of the pile structure, the alignment precision of the pattern and the composite performance influence brought by different yarn material combinations.

Tufted carpets: It is currently the most widely used carpet type, formed by implanting pile yarns into the backing fabric with a tufting machine. The testing focus is on the pile height, density uniformity, environmental friendliness of the backing adhesive, and the anchoring strength between the pile and the primary backing.

Needle-punched carpets: Made by reinforcing the fibre web through the needle-punching process, mostly used in industrial or commercial fields. Their testing focuses on the uniformity of the fibre web, tensile strength, abrasion resistance and the tolerance to oil, stains and chemical reagents.

Handmade carpets: Including hand-knotted carpets and hand-tufted carpets. In addition to conventional items, their unique process characteristics need to be focused on, such as the knot density, pattern symmetry, the natural characteristics of the handmade materials (such as the oil content of wool) and the characteristics of the natural dyes that may be used.

Carpet backing materials: Including the primary backing (such as polypropylene fabric) and the secondary backing (such as latex, polyurethane foam, bitumen or cork). Their dimensional stability, bonding strength with the pile, release of hazardous substances (especially the TVOC of the foam backing), microbial resistance and slip resistance need to be tested independently.

Modular carpet tiles: As modular paving products, in addition to the performance of the material itself, their testing scope also needs to cover special items such as the strength of the seams, dimensional tolerances, edge treatment quality and the colour consistency of products of different batches.

Testing Methods

Combustion test method: Mainly in accordance with standards such as ISO 9239-1 (radiant heat source method), GB/T 11785 or ASTM E648 (critical radiant flux method) and GB/T 11049 (tablet test method). By simulating different fire source conditions, the flame spread rate and flame retardancy grade of the carpet are quantitatively evaluated, providing data support for the building fire protection code.

Instrumental analysis method: Used for hazardous substance testing. For example, high-performance liquid chromatography (HPLC) is used to determine the formaldehyde emission; gas chromatography-mass spectrometry (GC-MS) is used to analyze TVOC and specific volatile organic compounds; atomic absorption spectroscopy (AAS) or inductively coupled plasma mass spectrometry (ICP-MS) is used to detect the extractable heavy metal content.

Physical property test method: A Taber abrasion tester (such as ASTM D3884) is used to evaluate the abrasion resistance; a universal material testing machine is used for strength tests such as tension, peeling and tuft withdrawal; the Martindale method (such as ISO 12947) is used to test abrasion resistance and appearance change; a dimensional stability test chamber is used to simulate temperature and humidity changes and measure the dimensional change rate.

Colour fastness rating method: Usually in accordance with the ISO 105 or GB/T 3920 standard series. A xenon arc lamp light fastness tester is used to simulate light exposure; a rubbing fastness tester is used for dry/wet rubbing tests; the change in colour and staining grades are compared with grey scales or instrumental colorimetry for objective rating.

Electrostatic property test method: Mainly in accordance with GB/T 12703.1 or ANSI/ESD STM 7.1 standards. Common methods include using a surface resistance tester to measure the resistance value under specific temperature and humidity, or using an electrostatic decay tester to measure the time required for the surface electrostatic voltage of the sample to decay to half (the half-life).

Microbiological test method: In accordance with standards such as GB/T 20944 (antibacterial performance) or GB/T 24346 (anti-mold performance). Through the quantitative or qualitative inoculation method, under specific culture media and culture conditions, the inhibitory effect of the specimen on the growth of bacteria or mold is evaluated, and the antibacterial rate is calculated or the mold growth grade is observed.

Testing Standards

Domestic Standards:

1. GB/T 3920-2024, Textiles — Tests for colour fastness — Colour fastness to rubbing

2. GB 18401-2010, National general safety technical code for textile products

3. GB/T 3921-2008, Textiles — Tests for colour fastness — Colour fastness to washing with soap or soap and soda

4. GB/T 3922-2013, Textiles — Tests for colour fastness — Colour fastness to perspiration

International Standards:

1. ISO 105, Textiles — Tests for colour fastness

2. ISO 13934-1, Textiles — Tensile properties of fabrics — Part 1: Determination of maximum force and elongation at maximum force using the strip method

Note: The applicable standard can be selected according to the product use and customer trade requirements; standards agreed in the contract take precedence over general standards.

Testing Instruments and Equipment

Universal material testing machine: Used to precisely measure the mechanical properties of the carpet and its components such as tensile strength, elongation at break, peeling strength and tuft withdrawal force. The equipment is equipped with a variety of dedicated fixtures and sensors, and can set the loading rate and test mode according to different standards, outputting the stress-strain curve and key data.

Abrasion resistance and appearance retention tester: Represented by the Taber abrasion tester and the Martindale abrasion tester. The Taber tester applies wear through rotating grinding wheels and evaluates the mass loss; the Martindale tester carries out friction in a Lissajous track under a specified pressure, and is used to evaluate the pilling, appearance change and number of abrasion cycles of the fabric surface. It is the core equipment for evaluating the durability of carpets.

Combustion performance testing device: Including radiant panel test chambers (such as ISO 9239-1), critical radiant flux furnaces (such as ASTM E648) and vertical/horizontal burning test chambers. These devices can precisely control the heat flux, flame application method and test environment, and are used to scientifically evaluate the flame spread characteristics and flame retardancy grade of carpet materials.

Spectroscopic and chromatographic analysis instruments: Gas chromatography-mass spectrometry (GC-MS) is used for qualitative and quantitative analysis of the volatile organic compounds (VOC) released by the carpet; high-performance liquid chromatography (HPLC) is used to detect polar substances such as formaldehyde; atomic absorption spectrometers (AAS) or inductively coupled plasma mass spectrometers (ICP-MS) are used for highly sensitive detection of heavy metal elements.

Colour fastness and colour evaluation equipment: A xenon lamp weather resistance test chamber simulates full-spectrum sunlight for light fastness testing; a rubbing fastness tester is used for standardized rubbing operations; a spectrophotometric colorimeter is used to objectively and precisely measure the colour coordinates, colour difference and whiteness of the carpet, evaluating the colour consistency and the degree of colour change.

Environmental and electrostatic testing equipment: A constant temperature and humidity chamber is used for conditioning the sample before the test and for testing under standard atmospheric pressure; a surface resistance tester and an electrostatic decay tester are used to evaluate the electrical conductivity and electrostatic dissipation performance of the material; in addition, a dedicated slip resistance coefficient tester is used to evaluate the slip safety of the backing.