Maternity Clothing Testing

Maternity wear inspection mainly conducts scientific testing and analysis on formaldehyde content testing, pH value testing, decomposable carcinogenic aromatic amine dye testing, heavy metal content testing, colour fastness testing and burning 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

Formaldehyde content testing: The maternity wear may use the finishing agents containing formaldehyde during the production process to improve the properties such as the wrinkle resistance and anti-shrinkage. The testing is carried out in accordance with the GB 18401 or GB 31701 standards, and the free and hydrolysed formaldehyde contents are determined by the liquid chromatography method or spectrophotometric method. This indicator is crucial for safeguarding the health of the pregnant women and the foetus. If it exceeds the limit, it may cause the skin and respiratory tract irritation, and even affect the development of the foetus.

pH value testing: The acid and alkali substances remaining in the textile dyeing and printing processing may cause its pH value to deviate from the weakly acidic adaptation range of the human skin (pH 4.0-7.5). The testing method follows GB/T 7573, extracting the specimen with water and measuring the pH value of its extract. The maternity wear with an unqualified pH value will destroy the acid-base balance of the skin surface, and easily cause the discomfort such as the skin itching and allergy.

Decomposable carcinogenic aromatic amine dye testing: This testing is carried out in accordance with the GB 18401 Appendix C or GB/T 17592 standard, aiming to screen whether the garment fabric uses the azo dyes that can be reductively decomposed to release 24 kinds of specific hazardous aromatic amines. After being absorbed by the human body, these aromatic amines may induce cancer, and the risk is extremely high for the pregnant women. The testing usually adopts a gas chromatography-mass spectrometer for the qualitative and quantitative analysis.

Heavy metal content testing: Mainly detects the extractable heavy metals such as lead, cadmium, mercury, arsenic, chromium, cobalt and nickel. The heavy metals on the maternity wear may originate from the dyes, auxiliary agents or metal accessories. The testing is carried out in accordance with the GB/T 17593 series standards, using the equipment such as the atomic absorption spectrophotometer or inductively coupled plasma mass spectrometer. The heavy metals can enter the body through the skin contact or oral contact (such as biting the clothes), causing the potential harm to the nervous systems of the pregnant women and the foetus.

Colour fastness testing: This testing evaluates the fastness of the colour of the maternity wear under the conditions such as the rubbing, perspiration, washing and saliva. Including the colour fastness to rubbing, colour fastness to perspiration, colour fastness to water and colour fastness to saliva. Especially the colour fastness to saliva is strictly required for the infant and children products, and attention also needs to be paid to the maternity wear if it contains the accessories. For the garments with poor colour fastness, the dyes are easy to fall off and be absorbed through the skin, or contaminate the other clothes.

Burning performance testing: For some pyjama-type maternity wear, the burning performance needs to be evaluated to reduce the fire risk. The testing is carried out in accordance with the burning rate requirements specified in GB 31701, testing the spread speed of the fabric after ignition under the specific conditions. This indicator is particularly important for the loose and flowing home maternity wear, and is one of the mandatory safety items.

Testing Scope

Maternity tops and dresses: Including the T-shirts, shirts, sweaters, coats and various dresses worn during the pregnancy. The testing focus covers the inner fabrics directly contacting the skin, such as the fabrics of the chest, abdomen and back. Attention needs to be paid to whether the formaldehyde, pH value, colour fastness and the elasticity and air permeability of the fabric meet the needs of the body shape changes and comfort during the pregnancy.

Maternity trousers and skirts: Such as the maternity support trousers, leggings, maternity jeans and skirts. In addition to the basic safety indicators, special attention needs to be paid to the durability and safety of the waist and abdomen adjustment belts and elastic bands, avoiding the hazardous substances in the accessories such as the metal buttons and zippers. Due to the frequent friction of the trousers, their colour fastness to rubbing and the abrasion resistance of the fabric are also the testing key points.

Maternity underwear and home wear: Including the maternity bras, underwear, nursing bras and home pyjamas. These products contact the skin most closely, and may be contacted by the baby during the nursing period, so the requirements for the formaldehyde, pH value, decomposable aromatic amines, heavy metals and colour fastness are extremely strict. The burning performance of the home wear is also within the testing scope.

Maternity protective clothing: Such as the radiation protection clothing (a non-mandatory standard product). If the radiation protection function is claimed, the shielding effectiveness of its claimed function needs to be tested in accordance with the relevant enterprise standards or association standards. At the same time, as a textile product, it still needs to meet all the mandatory safety requirements of GB 18401 and GB 31701.

Garment accessories and decorations: The testing scope extends to the buttons, zippers, webbings, laces, prints, embroidery threads and various decorations on the maternity wear. It needs to be ensured that these small parts have no sharp edges and sharp points, preventing the mechanical injury; at the same time, their heavy metal contents (such as the nickel release amount) and the migration of the dyes are detected, preventing the hazardous substances from entering the human body through the contact or biting.

Packaging and marking conformity: The testing scope also includes the packaging materials and durable labels of the product. The packaging materials should not have the migration risk of the hazardous substances. The labels need to comply with the requirements of GB/T 5296.4 and GB 31701, clearly marking the safety category of the product (the maternity wear is usually category B or higher), composition content, maintenance methods and manufacturer information, ensuring the information is true and compliant.

Testing Methods

Gas chromatography-mass spectrometry method (GC-MS): This method is mainly used to detect the decomposable carcinogenic aromatic amine dyes. After the sample undergoes the reductive cleavage pre-treatment, the generated aromatic amines are extracted, and enter the GC-MS system after the derivatization or directly for the separation and qualitative and quantitative analysis. This method has high sensitivity and good selectivity, and is the arbitration method specified in the international and domestic standards.

High-performance liquid chromatography method (HPLC): Widely applied to the quantitative detection of the formaldehyde content (the determination link after the acetylacetone method) and the screening of some prohibited dyes. The principle is to use the liquid as the mobile phase, separate the components to be measured in the chromatographic column, and then determine them through the detector. The HPLC method has a high degree of automation and good reproducibility, and is suitable for the precise analysis of the trace hazardous substances in the complex matrices.

Atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS): The AAS method is the traditional method for detecting the heavy metal contents in the textile, carrying out the quantification by measuring the absorption of the ground state atoms to the characteristic spectrum. The ICP-MS method has higher sensitivity, lower detection limit and the simultaneous multi-element analysis ability, and is the current mainstream technology for the trace and ultra-trace heavy metal analysis, which can more effectively safeguard the safety of the maternity wear.

Spectrophotometric method: This is a quantitative analysis method based on the selective absorption of the light by the substances. In the maternity wear testing, it is commonly used for the pH value determination (measuring the absorbance change of the extract corresponding to the pH value) and the formaldehyde content determination (such as the acetylacetone colour development method). This method has popularized equipment and relatively simple operation, and is the conventional testing means of the laboratory.

Colour fastness instrumental rating and grey scale comparison method: The colour fastness to rubbing is tested with a rubbing fastness tester; the colour fastness to perspiration, water and saliva is tested by treating the specimen under the specific conditions. After the treatment, a colorimeter or standard light source cabinet is used to rate the grade by comparing the change in colour of the specimen and the staining of the adjacent fabric with the grey scales or blue wool standards, ensuring the objective and accurate evaluation.

Burning performance testing method (vertical method): In accordance with the GB 31701 Appendix B, the specimen of the specific size is vertically hung in the burning test chamber, ignited on its lower edge with a specified flame for a certain time, and the afterflame time, afterglow time and damaged length are recorded, calculating the burning rate. This method simulates the burning behaviour of the garment in the vertical state, and is the key experiment for evaluating its fire hazard.

Testing Standards

Domestic Standards:

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

2. GB 31701, Safety technical code for infants and children textile products

3. GB/T 2912.1, Textiles — Determination of formaldehyde — Part 1: Free and hydrolysed formaldehyde (water extraction method)

4. GB/T 7573, Textiles — Determination of pH of the aqueous extract

5. GB/T 17592, Textiles — Determination of prohibited azo dyes

6. GB/T 17593, Textiles — Determination of heavy metals

International Standards:

1. ISO 105, Textiles — Tests for colour fastness

2. OEKO-TEX® Standard 100, General and special conditions for the authorisation to use the OEKO-TEX® Standard 100 mark

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

Gas chromatography-mass spectrometer (GC-MS): This equipment is composed of a gas chromatograph and a mass spectrometer in series, and is the core instrument for detecting the decomposable aromatic amines. The gas chromatograph realizes the efficient separation of the complex mixtures, and the mass spectrometer provides the molecular structure information of the separated components, realizing the precise qualitative analysis (comparison with the spectrum library) and quantitative analysis (selected ion monitoring), ensuring the reliable detection results.

Inductively coupled plasma mass spectrometer (ICP-MS): An ultra-high sensitivity equipment for the trace heavy metal detection. The sample solution enters the high-temperature plasma after atomization and is completely ionized, and the ions are separated and detected by the mass analyser according to the mass-to-charge ratio. Its detection limit can reach the ppt (ng/L) level, and can rapidly analyse dozens of elements at the same time, comprehensively evaluating the heavy metal safety risk of the maternity wear.

UV-visible spectrophotometer: Used to measure the absorbance of the solution to the light at a specific wavelength in the items such as the formaldehyde and pH value testing. The instrument usually includes the light source, monochromator, sample cell and detector. By measuring the absorbance of the solution after the colour development reaction and comparing with the standard curve, the concentration of the substance to be measured can be calculated. It is the basic and essential analysis instrument of the laboratory.

pH meter and extraction oscillator: The dedicated equipment combination of the pH value testing. The precision pH meter is equipped with a combined electrode, used to precisely measure the pH value of the aqueous extract of the specimen. The extraction oscillator is used to carry out the oscillating extraction of the specimen under the standard specified conditions (specific temperature, time and liquid ratio), ensuring that the substances to be measured are fully and uniformly transferred to the solution, guaranteeing the representativeness of the testing.

Colour fastness testing series equipment: Including the dedicated equipment such as the rubbing fastness testing machine, perspiration fastness tester and washing fastness testing machine. These equipment can precisely simulate and control the experimental conditions such as the friction pressure, number of times, test solution composition, temperature and time, ensuring the repeatability and reproducibility of the colour fastness testing. They are the key tools for evaluating the fixation performance of the dyes.

Vertical burning tester: A professional safety testing equipment for evaluating the burning performance of the maternity wear. Mainly composed of a sealed burning test chamber, specimen clamping device, automatic igniter, timer and exhaust system. It can precisely control the flame height and ignition time, and automatically record the afterflame and afterglow times, providing the objective data for judging the flame retardant safety of the product.