Halogen Testing Service for Electronics and Electrical Appliances

Halogen Test

1、Introduction to Halogens

Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At) are collectively referred to as halogens. Since astatine is a radioactive element and is almost non-existent in products, the first four elements are present in products, especially in polymer materials, in the form of organic compounds. Therefore, the halogens commonly referred to are only: fluorine, chlorine, bromine, and iodine. Halogens are widely used in flame retardants (PBB, PBE, TBBP-A, PCB, hexabromocyclododecane, tribromophenol, short-chain chlorinated paraffins), refrigerants, solvents, organic chemical raw materials, pesticides, bleaching agents, wool degreasing, etc. Most halogen compounds used in industry are organic halogen compounds, many of which are classified as chemicals harmful to humans and the environment, and are prohibited or restricted in use, making them key pollutants controlled by countries worldwide.

2、Which Products May Contain Halogens

(1) Flame Retardants

Halogen compounds are widely used in various plastic additives. For example, polybrominated biphenyls (PBB), polybrominated diphenyl ethers (PBE), tetrabromobisphenol A (TBBP-A), polychlorinated biphenyls (PCB), hexabromocyclododecane (HBCCD), tribromophenol, and short-chain chlorinated paraffins (SCCP) can be added to PVC, PU, polyester, and epoxy resins as flame retardants; they can be added to ABS, PS, PVC, PU, EVA, PE, and PP as foaming agents; chlorinated paraffins can also be used as plasticizers for plastic materials.

Flame retardants are additives that prevent the ignition of flammable materials or inhibit the spread of flames. The 1970s to 1980s were the golden period for the development of flame retardants worldwide, especially in Europe and the United States. During this time, the United States enacted several flame retardant regulations, providing a significant boost to the flame retardant market. Halogen-based (mainly brominated flame retardants) flame retardants have advantages such as high efficiency, low usage, high performance, and low cost. Additionally, the addition of halogen-based flame retardants has minimal impact on the inherent physical and mechanical properties of the base material, leading to rapid development with an annual growth rate of up to 20%. However, the use of halogen-based flame retardants also has disadvantages: in the event of a fire, the incomplete combustion of halogenated flame retardants produces large amounts of carcinogenic substances, as well as significant smoke and toxic corrosive gases, which can hinder firefighting and evacuation efforts and corrode equipment and instruments.

Therefore, many countries have enacted laws and regulations to control the use of halogen-based flame retardants. For example, the well-known EU RoHS Directive (Restriction of Hazardous Substances in Electrical and Electronic Equipment, 2002/95/EC) restricts the use of two types of brominated flame retardants: polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE). Other regions and countries with RoHS-related regulations also restrict the use of these two brominated flame retardants. Additionally, EU Directive 2003/11/EC restricts the use of pentabromodiphenyl ether and octabromodiphenyl ether, while Directive 2002/45/EC imposes restrictions on short-chain chlorinated paraffins. Norway's PoHS regulation (Prohibition on Certain Hazardous Substances in Consumer Products) draft also proposes restrictions on the use of medium-chain chlorinated paraffins, hexabromocyclododecane, and tetrabromobisphenol A. In the United States, several states began banning the use of pentabromodiphenyl ether, octabromodiphenyl ether, and decabromodiphenyl ether in products in early 2006.

(2) Polyvinyl Chloride (PVC)

Polyvinyl chloride (PVC) is one of the most common plastics on the market, known for its good flame retardancy, high resistance to acid and alkali corrosion, and excellent mechanical strength and electrical insulation. It is widely used in wire sheathing, panels, pipes, shoe soles, toys, doors and windows, stationery, and other industries. However, its heat resistance is poor, with a softening point of 80°C. It begins to decompose and discolor at 130°C, releasing acidic hydrogen chloride (HCl) gas. In the event of combustion, it also releases other toxic substances, such as dioxins. Direct incineration or landfilling of PVC waste can pollute soil and water sources. The raw material for producing PVC, vinyl chloride monomer, is also a carcinogen, and its residual presence in finished PVC products poses health risks to producers and users. Additionally, many PVC products use additives such as lead, cadmium, and phthalates to enhance performance, all of which are considered harmful.

(3) Ozone-Depleting Substances

Refrigerants, such as Freon, are used in refrigeration equipment like refrigerators and air conditioners. Most of these refrigerants are composed of chlorofluorocarbons (CFCs), which are halogen compounds. Many of these refrigerants damage the ozone layer and are classified as ozone-depleting substances (ODS). Another type of substance used as a fire extinguishing agent in fire suppression systems or portable fire extinguishers—halons—is also a halogen compound that damages the ozone layer. When ozone-depleting substances are exposed to solar radiation in the atmosphere, they decompose into halogen free radicals. These chemically active radicals combine with ozone, taking away an oxygen atom from the ozone molecule, triggering a destructive chain reaction that depletes ozone, reduces ozone concentration, and creates ozone holes.

Therefore, many countries and regions have enacted corresponding restrictions to reduce the environmental damage caused by these substances. In March 1985, representatives from 21 governments signed the Vienna Convention for the Protection of the Ozone Layer in Vienna, Austria, marking the beginning of international unified action to protect the ozone layer. To implement international control over the production and use of CFCs and other ODS, representatives from 24 governments signed the Montreal Protocol on Substances that Deplete the Ozone Layer in Montreal, Canada, in 1987, restricting the use of five chlorofluorocarbons (CFCs) and three halons, requiring countries to take action to phase out these substances and strengthen research and development of alternatives. China also signed this convention in 1991.

(4) Persistent Organic Pollutants (POPs)

Persistent organic pollutants are organic chemicals that persist in the environment for long periods, have long half-lives, accumulate through the food chain, and adversely affect human health and the environment. These substances are highly toxic, persistent, accumulative, and highly mobile. Therefore, in 2001, multiple countries signed the Stockholm Convention on Persistent Organic Pollutants in Stockholm, Sweden. The convention came into force on May 17, 2004, and took effect in China on November 11, 2004. The Stockholm Convention prohibits or restricts the use of 12 persistent organic pollutants, including eight organochlorine pesticides (aldrin, chlordane, dieldrin, endrin, heptachlor, mirex, toxaphene, and DDT), two industrial chemicals (hexachlorobenzene and polychlorinated biphenyls), and two dioxin-like substances (polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans), all of which are halogen-containing organic compounds with significant impacts on human health and the environment. The entry into force of this convention means that the use of these compounds will be comprehensively restricted worldwide until they are completely banned.

It is also worth noting that the Stockholm Convention includes several other organic halogen compounds on its candidate list: chlordecone (Kepone), hexachlorocyclohexane (a-, b-, g-, HCH), perfluorooctane sulfonate (PFOS), pentachlorobenzene, short-chain chlorinated paraffins (SCCP), hexabromobiphenyl (HxBB), pentabromodiphenyl ether (PentaBDE), and octabromodiphenyl ether (OctaBDE).

(5) Other Halogen Compounds

Polychlorinated biphenyls (PCBs) and polychlorinated terphenyls (PCTs) are two types of chemically stable substances that are difficult to decompose in nature. Due to their high persistence in the environment, they pose serious environmental hazards, particularly polluting water bodies and the atmosphere. To reduce their environmental impact, the EU has imposed restrictions on their use under Directive 76/769/EEC (Restriction of Hazardous Substances).

3、Analysis of Global Halogen-Free Trends

From Freon to POPs, from PVC to brominated flame retardants (BFR), the harm of organic halogen compounds to human health and the natural ecological environment is an indisputable fact. Organic halogen compounds themselves are highly toxic, and the incineration of waste containing such organic compounds can cause secondary pollution, producing highly toxic organic substances like dioxins. Dioxins refer to polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Therefore, it is essential to restrict the use of halogen-containing organic compounds.

In fact, developed countries have long initiated the "halogen-free" process, with minimal use of halogen-based flame retardants, replaced by inorganic flame retardants. For relevant enterprises in China, adapting to the international "halogen-free" trend and producing "halogen-free" products can effectively enhance their competitiveness, increase product added value, and is a necessary path to meet international market demands!

4、Regulatory Controls

EU's 2002/95/EC (RoHS Directive), 76/769/EEC, 2003/11/EC, Norway's PoHS, and relevant laws in various U.S. states impose restrictions on certain specific halogen compounds.

（1）EU 2011/65/EU - Restricts the use of brominated flame retardants (PBB ≤ 1000 mg/kg, PBDE ≤ 1000 mg/kg)

（2）Global Montreal Protocol - Restricts the use of five chlorofluorocarbons (CFCs) and three halons

（3）Stockholm Convention (151 countries and organizations) - Restricts the use of organochlorine pesticides, hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs)

（4）IEC Standard IEC 61249-2-21 for Printed Board Materials - Requires that in printed circuit boards and other interconnect component materials, reinforced substrates for flammability (vertical burning test) of copper-clad laminates, and halogen-free epoxy electronic glass fiber reinforced laminates used in composite and non-composite materials: chlorine (Cl) ≤ 900 mg/kg, bromine (Br) ≤ 900 mg/kg, total halogens (Cl + Br) ≤ 1500 mg/kg

（5）Japan Printed Circuit Association (JPCA) Standard JPCA-ES-01-1999 defines "halogen-free" and sets standards, requiring that the total amount of bromine (Br) in printed circuit boards (PCBs) must not exceed 900 ppm, and the total amount of chlorine (Cl) must not exceed 900 ppm. The standard was revised in 2003 to add a new requirement that the total amount of bromine and chlorine must not exceed 1,500 ppm.

（6）IPC Standard IPC-4101B - Sets requirements for rigid multilayer printed circuit board substrates, stipulating that the total amount of bromine (Br) must not exceed 900 ppm, the total amount of chlorine (Cl) must not exceed 900 ppm, and the total amount of bromine and chlorine must not exceed 1,500 ppm.

5、Testing Methods

（1）Halogen XRF Rapid Testing

（2）Chemical Testing for Halogen Elements

（3）Chemical Testing for Specific Halogenated Organic Compounds

（4）Halogen Whole-Machine Verification

（5）PVC Composition Analysis

6、Main Testing Content

Heavy metal testing, halogen testing, ultraviolet testing, lead content testing, phthalate testing, dimethyl fumarate testing, azo testing, perfluorooctane sulfonate/PFOA testing, formaldehyde, benzene, TVOC, radon testing, aflatoxin testing, plasticizer testing, pesticide residue testing, food additive content testing, ELV testing and atomization testing, volatile organic compound testing, polycyclic aromatic hydrocarbon testing, fluorescent agent testing, ROHS/REACH/SVHC/POSH/WEEE testing, solid waste hazardous waste testing, solid waste, liquid waste, etc.