Electromagnetic radiation protective clothing increasingly becomes the focus of the textile industry

Electromagnetic radiation refers to the emission or leakage of electromagnetic waves into the air. When it comes to the potential harm of electromagnetic radiation to the human body, there are various academic opinions both domestically and internationally. Regarding the dangers posed by electromagnetic radiation, we should neither ignore its effects nor overstate them.

With the rapid advancement of information technology, textile materials must now consider their electromagnetic wave transmission properties more thoroughly. As the "people-oriented" concept becomes more widespread and individual electromagnetic protection needs increase, textiles—commonly used as protective materials for the human body—must be studied for their electromagnetic shielding capabilities while also taking into account thermal and moisture permeability and overall comfort. Therefore, starting from the requirements of electromagnetic compatibility, electromagnetic shielding, electromagnetic stealth, radar reconnaissance, camouflage, and electronic warfare, it is essential to conduct research on textiles with special electromagnetic properties based on complex structures and the integration of other materials. This will enrich the scientific content of textile electrical performance studies and lay the foundation for the development of advanced electromagnetic textiles with specific functions.

Where do you start developing electromagnetic radiation protection materials?

Academician Zhou Guotai of the Chinese Academy of Engineering stated, “The current research status in electromagnetic radiation protection materials focuses on the development of new materials that are 'light, soft, thin, and wide'—emphasizing lightweight, flexibility, thinness, and broadband characteristics. The use of a gradient structure helps absorb and reflect electromagnetic waves, achieving high shielding effectiveness.”

Although not all forms of radiation are harmful to the human body, in today's world where electromagnetic radiation is everywhere, electromagnetic radiation protective clothing has become a key piece of personal protective equipment and is gaining increasing attention within the textile industry and among consumers.

What progress has the industry made in researching electromagnetic radiation shielding materials? Dr. Shi Wei, a senior engineer at the Military Equipment Research Institute under the General Logistics Department, provided a detailed explanation: “In addition to stainless steel wire blended fabrics, electroless silver-plated fabrics, electroless copper (nickel) fabrics, conductive acrylic fabrics, and multi-ion fiber fabrics, researchers have also explored using tin instead of nickel to avoid heavy metals. They have woven appropriate dimensions and microfiber counts on synthetic fiber base fabrics used for metallization treatments. This ensures that electromagnetic waves above a certain frequency cannot enter the garment through micropores. The final product considers both the shielding effectiveness and wearing comfort of the protective suit, especially when high shielding effectiveness is required. Since such protective clothing must be designed as an electrical seal, it may lead to issues with air permeability and comfort. Thus, using porous fabric metallization treatment can help achieve both protection and comfort.”

In addition, researchers have designed skin-core structured fabrics for metallization. The core layer consists of conventional polyester, while the skin layer is a blend of ordinary polyester and spun into a composite sheath-core filament. After alkali reduction treatment, the fabric surface develops many pits, which allows for metallization on the uneven fiber surface. The metal layer, riveted into the fiber pits, prevents detachment due to the riveting effect, resulting in better durability of the metalized fabric.

Standards Need to Be Improved

Zhou Guotai emphasized that formulating a scientific and reasonable exposure limit is crucial for determining whether the environment people live in is basically safe (excluding electromagnetically sensitive individuals), whether electromagnetic radiation in the working environment requires protection, and how much shielding effectiveness should be included in protective clothing. It serves as the fundamental basis for these decisions.

Since 1988, the Ministry of Health, the National Environmental Protection Agency, and the Ministry of Electronics have drafted six national standards for electromagnetic radiation. In response to the issue of outdated standards and unclear content, the General Armament Department merged seven military standards related to electromagnetic protection established since 1984. This led to the redefinition of the "exposure limit" concept in the GJB 5313 standard, "Electromagnetic Radiation Exposure Limits and Measurement Methods," which was officially released in 2004.

"The two 'Electromagnetic Radiation Exposure Limits and Measurement Methods' standards, after being merged and unified, serve as the basic basis for China’s allowable intensity of environmental electromagnetic fields and human exposure limits. Although one of them is a national standard, it remains in the draft stage. However, its technical content is still reliable, as it builds upon the previous six national standards. If there are uncertainties, it's mainly because different management departments take different perspectives, leading to variations in exposure limit requirements," said Shi Yong. He believes that the exposure limit value of GJB 5313 is moderately stricter than the previous draft and can be used as a “superior standard” for designing the shielding effectiveness of electromagnetic radiation protective clothing.

The newly developed GB/T 23463-2009 standard, "Protective Clothing – Microwave Radiation Protective Clothing," stipulates that the shielding effectiveness of electromagnetic radiation protective clothing should be determined according to the exposure limits of GJB 5313 and the field strength of electromagnetic radiation in the workplace.

Similarly, whether the public needs to wear electromagnetic shielding protective clothing depends on the conclusions drawn from the exposure limits of the corresponding frequency and the actual electromagnetic field strength of the environment as proposed by the standard.

Clear Concept Awareness

Regarding the development trends of electromagnetic radiation protection, the two experts have the following suggestions: First, increase the knowledge level of the public and professionals through science education so that they understand concepts such as electromagnetic radiation, damage mechanisms, and exposure limits, and strictly control exaggerated media reports about electromagnetic radiation hazards.

Second, clearly distinguish between ionizing and non-ionizing radiation, gradually changing the term “electromagnetic radiation” to “electromagnetic exposure” to emphasize that for non-ionizing radiation, the harm is not as severe as ionizing radiation. Human exposure to microwaves is similar to exposure to light waves. In fact, the wavelength of electromagnetic waves is longer than visible light, and the damage is not as significant.

Third, establish a unified national standard for electromagnetic radiation limits as soon as possible and formulate a national law for the prevention and control of electromagnetic radiation pollution.

Fourth, develop scientific and specific product standards and usage methods for pollution sources prone to electromagnetic wave leakage and often used by the public, such as induction cookers and microwave ovens, to prevent substandard products with severe electromagnetic wave leakage from entering the market. Encourage the use of compatible accessories like pots and utensils to ensure safe and proper usage.

Fifth, formulate relevant laws and regulations, set strict provisions for electromagnetic radiation protective clothing for workers, and require mandatory use of protective clothing if the exposure limit in the work environment is exceeded, in accordance with the GB/T 23463-2009 standard.

Build Responsible Brands to Promote Sustainable Consumption

The new era has brought new demands for social responsibility in the industry. In 2014, the China National Textile and Apparel Council focused on the global economic environment and the development of the industry. Based on previous efforts in social responsibility, the China Textile Industry Federation proposed a new initiative for the construction of a social responsibility system for the Chinese textile and garment industry: building responsible brands and promoting sustainable consumption.

Today, fulfilling social responsibilities and achieving sustainable development are issues every industry must address during its growth. Guiding and encouraging enterprises to fulfill their social responsibilities and boosting the industry toward sustainable development have been key priorities for the sector.

Over the past decade, under the organization and advocacy of the China Textile Association, with active cooperation from industry and enterprises, and joint efforts and support from relevant parties, the social responsibility construction of China’s textile and garment industry has gained recognition both domestically and internationally, opening up a strategic path for sustainable development.

China’s textile and garment industry was the first in China to advocate for social responsibility and build a corporate social responsibility implementation system. In 2005, the China Textile Association launched China’s first standardized social responsibility management system, csc9000t. To date, it has promoted and implemented this system across over 300 key textile and garment enterprises, obtaining approval from international social responsibility standards such as BSCI in Europe and SA8000 in the United States.

In 2008, the China Textile Association also launched China’s first guideline for preparing social responsibility reports. To date, over 60 companies have issued social responsibility reports on industry platforms, causing significant impact at both the international supply chain and domestic policy levels.

To promote deeper and broader social responsibility experiences in the industry, build collaborative forces for sustainable development, and respond to new expectations from domestic and foreign consumers and supply chain partners, the China Garment Association and the China Textile Association’s Social Responsibility Office launched the “China Apparel Industry Social Responsibility Collective Action Project” in early 2014, with the theme of “Responsible Brand, Sustainable Consumption.” It received positive responses from numerous brand enterprises and leading companies in the home industry.

The project was formally launched in March 2014, divided into three phases: issuing industry advocacy, releasing social responsibility reports by apparel companies, and evaluating reports and providing feedback on enterprise management. It lasted for six months. Through the joint publication of the “China Declaration on the Social Responsibility of the Garment Industry in Collective Action” and collective participation in the “report-based responsibility improvement” process, the project integrated top-down actions and promoted coordinated accountability among industry companies in the field of social responsibility. This fostered virtuous competition in performance and strengthened and tapped the social responsibility management capabilities and sustainable development potential of garment enterprises.