Test method for flame retardant protective clothing

Flame retardant protective clothing refers to the direct contact with the flame and hot objects, can slow the spread of the flame, carbonization to form a protective layer to protect the safety and health of a protective clothing. Every year, tens of thousands of people in the world are burned by improper clothing, and found that the most serious burns are often caused by the burning of clothes rather than the flame itself, the burning of clothing under the skin burns are often more serious than the direct exposure of the skin The As a protection of workers living safety and health of a human protective equipment, fire retardant protective clothing is widely used in metallurgy, petrochemical, welding and other industries, with people's safety awareness and protection of knowledge and the development of domestic protective clothing production The application of fire protective clothing is expanding. In the case of
The thermal protection performance of the flame retardant protective clothing is generally to determine the advantages and disadvantages of the flame retardant properties of the garment material. In addition to the flame retardant properties, thermal protective clothing insulation, integrity and resistance to liquid permeability is also an important indicator to determine the thermal protection performance of flame retardant protective clothing. Some technologically advanced countries such as the United States, Europe, Australia and other countries and regions have developed a more complete assessment of the flame retardant performance test methods.
1 American Fire Association standards
1.1 NFPA 1971
NFPA 1971 is a complete set of equipment for firefighters in construction fire fighting. It sets out the minimum requirements for firefighters in building fire, including costume design, safety performance and clothing components and ancillary items (tops, pants, helmets, gloves, Of the comprehensive testing. Among them, the thermal protection performance test (TPP method) is measured by the heat source through the fabric and other materials to the surface of the human body, resulting in secondary burns required heat, according to the fabric to evaluate the thermal protection performance. The method of operation is: the heat source is placed on the side of the test sample, and the heat meter is placed on the other side. There is a movable insulation board between the heat source and the tested sample. The heat shield and the test specimen are usually insulated. Open, the test sample is exposed to the heat source, by measuring the calorific value of a calorimeter for a certain period of time to measure the heat flux of the sample and record the time required to achieve the second burn, so that the thermal protection index TPP value.
1.2 NFPA 1975
NFPA 1975 for the fire and emergency protective clothing test standards, commonly used in industrial flame retardant protective clothing to determine the flame retardant properties. Protective clothing fabric flame retardant properties using vertical combustion test method. In addition, the 500 ° F oven test method is used to determine the thermal stability of the material. It is required to place the material in a 500 ° F high temperature oven for 5 min, where the shrinkage rate can not exceed 15%, and then depending on whether the material will ignite, Or decomposition to determine other thermal protection performance.
1.3 NFPA 2112
NFPA 2112 is the standard for industrial fire-retardant protective clothing and is the basis for the establishment of future industrial fire-retardant protective clothing laws and regulations. It describes the industrial thermal protection protective clothing thermal protection performance requirements, including a series of thermal protection performance test.
(1) vertical burning performance test. Expose the material to the standard flame for 12 s, remove the flame and determine whether it will be ignited and burned to damage the length.
(2) thermal radiation and thermal convection mixed protective performance test, referred to as TPP method. This method tests the placement of a 6-square-inch fabric under the thermal convection and radiant heat source with a total energy density of 2 cal / (cm2 • s) and then records the time required for secondary burns. The TPP value is the time With a value of cal / cal / (cm2 • s). The higher the TPP value, the stronger the protection provided by the fabric. In contrast to the vertical burning test, the TPP test can tell us how much of the energy to be absorbed by the simulated skin of the human body through a variety of different fabrics, that is, the higher the TPP value, the cloth is exposed to high temperatures and high thermal flames The better the protection of the body, the unit TPP value is the most direct manifestation of thermal protection performance.
(3) thermal human body model test. The test was conducted in a 2 cal / cm2 • s heat source with a 6-inch high body model containing 122 temperature testers and exposed to a 12 propane flamethrower. A temperature tester to collect the data, to simulate the human skin may be subject to the secondary and tertiary burns and parts. This is the most advanced thermal burn evaluation system in the world today. In order to further simulate the degree of burns in the human body in actual flames, it is used to test the degree of protection that the clothes can provide in simulating the actual flame condition. Through this test, we can predict the body may reach the secondary or tertiary burns, the lower the degree of systemic burns, the greater the chance of survival.
(4) The thermal stability test is essentially the same as the 500 ° F oven test in the NFPA 1975 standard.

2 EU standards
2.1 EN 531
EN 531 is the European Union Industrial Thermal Protective Clothing Standard. The standard of the overall performance of flame retardant protective clothing, structural design, dimensional stability, flame spread, heat and melt metal properties, size mark and mark, user information, identification patterns and other content provided for. The flame retardancy test was carried out using EN 532. EN 532 is a test method for limiting the rate of flame diffusion. The test method is to ignite the surface of the material for vertical placement for 10 s. The criteria are as follows:
(1) any specimen shall not have a burning spread to the edge of the fabric or the top of the fabric;
(2) any specimen shall not be formed by holes;
(3) any sample should not have a burning droplet or a melt falling;
(4) the duration of fueling shall be less than or equal to 2 s;
(5) The smoldering time shall be less than or equal to 2 s.
2.2 EN 470
EN 470 for the EU welder and similar types of thermal protection protective clothing standards, the provisions of the flame retardant protective clothing design requirements, material requirements, safety requirements, size marks and marks, user information, identification patterns. After the sample is washed or dried in accordance with the prescribed method, the combustion performance test of the fabric is carried out according to the EN 532 test method. In addition, the effect of falling on the fine droplets of metal is evaluated in accordance with EN 348. After the test sample is washed or dried, if the droplets of the average of 10 pieces are between 15 and 15.5 drops, the second 10 pieces shall be tested. The judgment shall be based on 20 pieces of cloth Of the average data.
2.3 EN 469
EN 469 for the EU fire protection clothing standards, the main consideration is the large fire in the heat and flame to protect, not including such as cleaning spill chemicals, forest fires, close fire, road accident relief and other special tasks or special fire protection use Of clothing. This standard covers the overall requirements for protective clothing, important safety requirements, additional requirements, marking marks, user information and identification patterns. In addition to fire resistance, the outer surface of the fabric must also have a certain physical properties to adapt to external environmental conditions, such as thermal stress. These basic safety properties include residual strength, heat resistance, tensile strength, tear strength, surface wettability and dimensional changes. The standard requires that the outer layer be exposed to a heat source with a daily flow density of 10 kW / m2, and the remaining strength of the outer layer fabric, i.e., the tensile strength and tear strength, must be greater than 450 N and 25 N, respectively. In addition, the standard also provides any fabric for fire protection clothing, must pass the heat resistance test. The test method is to place the sample in a constant temperature heating chamber at 260 ° F. The test specimen can not be melted, dripped or ignited and the shrinkage should be less than or equal to 5%.

3 Australian and Chinese standards
3.1 AS 4824-2001
AS 4824-2001 for Australia (transitional version) firefighters protective clothing standards. The standard specifies the design requirements for dressing and pretreatment methods for fire fighting personnel for field and forest firefighters, thermal protection performance requirements, mechanical performance requirements, manpower and comfort requirements, general requirements, manufacturer information and mark marks. Among them, the thermal protection performance requirements of the test method using EN 532 similar to the test method.
3.2 GB 8965-98
GB 8965-98 for the Chinese national flame retardant clothing standards. This standard applies to industrial furnaces, metal thermal processing, welding, chemical, petroleum and other places, engaged in a fire or sparks or in the vicinity of molten metal operation, and in the presence of combustible materials and the risk of working place Of the flame retardant protective clothing. The standard with reference to the same name in 1988 and international standards issued by the same standards of industrial flame retardant clothing, and the following aspects of the provisions of the overall performance of fire-retardant protective clothing, fabric and suture flame retardant properties, fire-retardant protective clothing The mechanical properties, structural design, processing, finished product labeling and packaging transport, inspection methods. The flame retardant performance test method of the fabric is GB / T 5455, which is similar to EN 532, which is ignited on the surface of the vertically placed material for 10 s, and then the fabric is divided according to the test parameters, the burning time, the smoldering time and the damaged length Three levels. After the flame retardant finishing fabric, to two qualified, one for the excellent products. Test fabric after 50 times after washing, not less than three, in the test found that the product has a melting contraction phenomenon for the defective products.
4 concluding remarks
China's flame-retardant textile performance testing methods are to close to the international standards commonly used, some are directly used, some are equivalent or equivalent, in the product standards are also towards the international and serialization direction. China's fire department has been for the firefighters general protective clothing performance requirements and test methods, fire insulation services, fire and fire protection clothing and fire protection service four products formed a series of industry standards. At present, in terms of the comprehensiveness and multiplicity of performance requirements, textile protection product standards in addition to the requirements of flame retardancy, has been applied to the development, such as clothing fabrics are strong, breathable (wet), stiffness, shrinkage, color and Toxicity and other requirements. In addition, depending on the use of different environments but also to increase the special protective performance requirements, welding service to increase the anti-molten metal drop impact requirements, fire suit to increase the anti-radiation and water resistance requirements, petrochemical and coal mine protective clothing to increase the antistatic And so on.
With the progress of science and technology, people's awareness of safety and self-protection awareness and the introduction of relevant laws and regulations, a variety of high-quality protection products will be widely accepted by the relevant industries, its research will be more and more in-depth. The future of protective clothing will continue to improve the quality and reduce costs, the use of new synthetic materials, set fire, anti-virus, anti-chemical and other protective functions as a whole, and to wear comfort development.

Xinxiang City Yulong Textile Co., Ltd. was established in 2002, over the years focused on the production of flame retardant, fluorescent-oriented variety of functional fabrics and security clothing. The company has afunctional fabric factory and protective clothing factory, as the domestic functional textile industry leader, Yu Long textile more groundbreaking integration of its fabric and clothing two factories of the advantages of resources, effort to build functional fabrics and clothing Station service center.