Halogen Free (HF) Policy
Background
"Halogen Free," also known as "halogen-free additives" or "dehalogenation," typically refers to the absence of halogens, namely Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At), which are the five non-metal elements of Group VIIA. Halogenated compounds are often used in flame retardants, plasticizers, colorants, and other functionalities such as polybrominated biphenyls (PBB), polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBP-A), hexabromocyclododecane (HBCDD), tetrabromophthalic anhydride (TBBPA), tribromophenol (TBP), short-chain chlorinated paraffins (SCCPs), etc. These compounds are widely used in electronic equipment, machinery enclosures, printed circuit boards, cables, electronic components and materials, product enclosures, packaging materials, plastics, etc.
Because these flame retardants cannot be recycled and release corrosive gases and other harmful substances during combustion and heating, they pose threats to the immune system, endocrine system, reproductive system, etc., and the accumulation of organic halides in the human body may also lead to cancer, all of which threaten human health. Volatile organic halides also have a significant destructive effect on the ozone layer, damaging the Earth's environment. Therefore, halogenated compounds are listed as harmful chemicals to humans and the environment, and countries are adopting corresponding methods to prohibit or limit their use, known as "halogen-free policies/directives." This mainly affects the electronics manufacturing industry, where electronics manufacturers are gradually being required to phase out halogenated compounds such as polyvinyl chloride (PVC) and brominated flame retardants (BFRs) from their products.
Not all components require testing. The published survey will indicate whether submission of this testing report is necessary. The required policies from system manufacturers can be accessed on the platform for reference.
Halogen-free Policy
International standards related to halogen restrictions:
The Montreal Protocol
Also known as the Montreal Protocol, the full name is the "Montreal Protocol on Substances that Deplete the Ozone Layer." It is a United Nations agreement aimed at preventing worsening and damage to the Earth's ozone layer caused by chlorofluorocarbons (haloalkanes composed of chlorine, fluorine, and carbon, also known as halocarbons) present in industrial products. The protocol came into effect on January 1, 1989. Regarding halogen-related restrictions, the protocol mandates a phased reduction in the consumption and production of five types of chlorofluorocarbons (CFCs) and three types of halons.
The Stockholm Convention
Adopted on May 22, 2001, in Stockholm, and effective as of May 17, 2004, the convention was jointly agreed upon by 151 countries and 128 organizations. It is an international treaty concerning environmental protection, with the aim of prohibiting or restricting the production of persistent organic pollutants (POPs) to protect human health and the environment from the harmful effects of these pollutants. The restricted substances include organochlorine pesticides, hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs).
E.U.
- RoHS Directive (2002/95/EC, 2011/65/EU): The usage of Polybrominated Biphenyls (PBB) and Polybrominated Diphenyl Ethers (PBDEs) is restricted to no more than 0.1%.
- EU Directives 79/663/EEC, 83/264/EEC, and 2003/11/EC: Prohibition of two brominated flame retardants.
Industry practices
Various international regulations prohibiting the use of hazardous halogenated substances in electronic and electrical equipment, toys, leather products, etc.
| Policy Name | Content |
|---|---|
| Industrial standard - IEC 61249-2-21 (International Electrotechnical Commission) | Brominated compounds: Content < 900 ppm Chlorinated compounds: Content < 900 ppm Total halogens: Content < 1500 ppm |
| Industrial standard - IPC (Association Connecting Electronics Industries) | Bromine compounds: Content < 900 ppm Chlorine compounds: Content < 900 ppm Total halogens: Content < 1500 ppm |
| Industrial standard - JPCA (Japan Electronics Packaging and Circuits Association) | Bromine compounds: Content < 900 ppm Chlorine compounds: Content < 900 ppm |
| International Manufacturer - Samsung | Brominated compounds: Content < 900 ppm Chlorinated compounds: Content < 900 ppm |
| International Manufacturer - Asus, Dell, HP (Hewlett-Packard), Apple, Intel, AMD | The introduction of halogen-free materials began in 2008. |
Halogen-free standard requirements within the scope of wires and cables typically include:
- Total halogen content ≤ 50 ppm (According to regulation PREN 14582)
- The content of hydrogen halide gas produced during combustion < 100 ppm (According to regulation EN50267-2-1)
- The pH value of gas acidity during combustion determination ≥ 4.3 (Weak acidity) (According to regulation EN50267-2-2)
- The light transmittance through a product during combustion in a sealed container ≥ 60% (According to EN50268-2)
The International Electrotechnical Commission (IEC) has also established standards defining halogen-free materials. Halogen-free cable compounds should meet the following requirements:
- HCL production ≤ 5mg/g (0.5%) (According to IEC 60754-1)
- pH value ≥ 4.3 (According to IEC 60754-2)
- Electrical conductivity ≤ 10 µS/smm (According to IEC 60754-2)
Understanding Halogens
Fluorine (Fluor-), Chlorine (Chlor-), Bromine (Brom-), Iodine (Iod-), and Astatine (Astat-) are the five elements collectively known as halogens. Astatine (Astat-) is a radioactive element, but when people refer to halogens, they typically mean fluorine, chlorine, bromine, and iodine.
Halogens compounds commonly used in industry are mostly synthetically produced organic halides. Their advantages include flame retardancy, solubility, and high reactivity.
Applications of halogens include: Flame retardants, Refrigerants, Solvents, Organic chemical raw materials, Bleaching agents, Pesticides and insecticides, Wool scouring agents
| Element | Characteristics | Applications |
|---|---|---|
| Fluorine(F) | Pale yellow gas (F2). A highly corrosive and strong oxidizing agent. It readily combines with other elements, releasing large amounts of heat energy. | Manufacture of Hydrofluoric acid (HF), plastics (Teflon, PTFE, PFA, FEP, etc.), production of insecticide NaF, addition to drinking water and toothpaste to prevent tooth decay. |
| Chlorine(Cl) | Green gas (Cl2). A strong oxidizing agent. It can irritate the mucous membranes of the respiratory tract and, in severe cases, can be fatal. | Manufacture of disinfectants and bleach. |
| Bromine(Br) | Red-brown liquid. It can cause severe burns upon skin contact. | Manufacture of disinfectants and bleaching agents, medical applications in anesthesia, sedation, and refrigerants; flame retardants for plastics, clarifiers, preservatives, and deodorants. |
| Iodine(I) | Purple solid. An essential trace element for living organisms. | Disinfectant iodine tincture and tungsten wire contain tungsten iodide. |
| Astatine(At) | Radioactive element. An unstable radioactive halogen with properties similar to iodine. It is found in trace amounts in the natural decay products of uranium and thorium minerals. | Due to the short half-lives of various isotopes of astatine, its compounds have little practical value. Its rarity and specific properties result in very few applications in everyday industrial products. |
Halon - Halon is a type of halogenated alkane, specifically referring to halogenated alkanes containing bromine. Halon is a very clean extinguishing agent that does not leave behind powder, foam, or water residue. Therefore, it is commonly used in close proximity to sensitive equipment and instruments, such as in airplanes, ship compartments, control rooms, and metro systems. However, due to concerns about the depletion of the Earth's ozone layer, halon, like other fluorinated chlorocarbons (such as refrigerants used in air conditioning), has been gradually phased out. Except for some specialized environments such as enclosed spacecraft, its use has become rare.
The hazards of halogens
These compounds can induce toxicity to the immune system, affect the endocrine system, reproduction, and development, exhibit carcinogenic properties, and are prone to triggering mental and psychological disorders. Most halogenated compounds act as endocrine disruptors, characterized by their toxic, lipophilic nature, and difficulty in biodegradation. Consequently, once they enter the biological system, they tend to accumulate, distribute throughout various organs via the bloodstream, and cause long-term and intricate damage. They interfere with normal cell division, disrupt the activity of enzymes, and lead to multiple diseases or physiological disorders. Moreover, organic halides may also synergize with heavy metals, enhancing their biological activity and consequently posing greater toxicity to organisms.
Products containing halogens
- Enclosures and structures, polymers such as plastics, nylon, electrical components, and foam materials
- Power and signal connectors
- Chemicals, insulation adhesive materials, buffering foam materials
- Plugs, sockets, connecting wires
- Plastic colorants, pigments
- Chemical inks, adhesive tapes
- PCB boards, FPC board
Main Applications of Halogens
Bromine-based Flame Retardants: PBBs, PBDEs, TBBP-A, HBCDD
Chlorine-based Flame Retardants: SCCP, MCCP, Chlorinated fatty naphthalene, Tetrachlorophthalic anhydride
Other organic halogenated compounds
- PCB (Polychlorinated Biphenyls): Lubricants, Capacitor Fluids
- PCN (Polychlorinated Naphthalenes): Lubricants, Preservatives
- PCT (Polychlorinated Terphenyls): Lubricants, Preservatives
- PVC (Polyvinyl Chloride): Plastic
- PCP (Pentachlorophenol): Preservative, Fungicide, Insecticide
- CFC (Chlorofluorocarbons), HCFC (Hydrochlorofluorocarbons), HALON: Foam blowing agents, aerosol propellants, refrigerants
Classification and Applications of Flame Retardants
- Brominated compounds: PBBs (Polybrominated Biphenyls), PBDEs (Polybrominated Diphenyl Ethers), TBBP-A (Tetrabromobisphenol A), HBCDD (Hexabromocyclododecane) exhibit excellent performance, with flame retardancy efficiency being more than twice that of chlorine-based flame retardants.
- Chlorinated compounds: CP (Chlorinated Paraffins), PCT (Polychlorinated Terphenyls), PCB (Polychlorinated Biphenyls) are characterized by low cost and wide applications.
- Phosphorus compounds: Inorganic phosphorus, phosphate esters, halogenated phosphate esters, and phosphorus halides are widely used. They are applied in phenolic resins, epoxy resins, polyesters, polycarbonates, polyurethanes, polyvinyl chloride (PVC), vinyl chloride, and acrylonitrile-butadiene-styrene (ABS).
- Inorganic flame retardants: Antimony trioxide, magnesium hydroxide, aluminum hydroxide, and boron compounds.
- Organic nitrogen-based flame retardants
**There are currently two types of flame retardants: **
Additive type: Physical structure, which affects the properties of the substrate, can be added in high amounts, but is easy to process; examples include PBBs and PBDEs.
Reactive type: Chemical bonding, involves chemically bonding the flame retardant to the substrate, resulting in good flame retardancy performance and low addition amounts; examples include TBBP-A.
Applications in electronic products
Brominated flame retardants such as PBB, PBDE, and TBBPA are currently widely used flame retardants, primarily applied in the electronics industry, including circuit boards, computers, fuel cells, televisions, and printers, among others.
- Engineering plastic components: Flame retardants such as brominated and chlorinated compounds, used in ABS/HIPS/PC/PS/PBT, etc.
- Cables: Brominated flame retardants are used in insulation materials for wires and cables, as well as in the sheathing and outer coatings of polyvinyl chloride (PVC) wires and cables.
- Electronic components: Brominated flame retardants are used in FR-4 epoxy resin, solder masks, molds, plastic packaging, thermal interface materials, encapsulation, and filling materials.
- Printed Circuit Boards (PCBs): Flame retardants for printed circuits, FR-4 epoxy resin, solder masks, cleaning agents for PCB processes, soldering fluxes, and other chemical products such as sodium chloride for commercial and engineering epoxy resins.
- Connectors: Brominated flame retardants in PBT and PA industrial resins.
- Film, adhesives, tapes, and polyester films: Brominated flame retardants in resins, PVC used in magnetic materials.
- Vibration-damping materials: PVC materials for vibration and shock absorption.
- Flux: Bromine and chlorine used in flux to improve soldering fumes.
- CFCs (Chlorofluorocarbons): Foam blowing agents, cleaning agents, propellants and solvents for dry cleaning or cleaning agents, aerosol propellants, refrigerants.
- HCFCs (Hydrochlorofluorocarbons): Plastic foam blowing agents, propellants, refrigerants.
- HFCs (Hydrofluorocarbons): Plastic foam blowing agents, refrigerants, propellants or solvents for dry cleaning or cleaning agents, aerosol propellants.
- CF2ClBr, C2F4Br2, CBrF3: Fire extinguishing agents
Applications in the plastics and wire industries
Adding halogens (fluorine, chlorine, bromine, iodine) to polymer products such as plastics is done to increase their ignition point. The advantage is that the ignition point is higher compared to regular polymer materials, typically around 300°C. During combustion, halogenated gases (fluorine, chlorine, bromine, iodine) are emitted, which rapidly absorb oxygen, extinguishing the fire. However, the disadvantage is that high concentrations of released chlorine gas can reduce visibility, making escape routes difficult to identify. Additionally, chlorine gas is highly toxic and can affect the respiratory system. Furthermore, when halogen-containing polymers burn, the released halogen gases combine with water vapor to form corrosive and harmful gases (hydrogen halides), leading to corrosion of some equipment and buildings.