Halogen-free
Halogens can represent significant hazards for humans and the environment. Some halogens form toxic gases, particularly in the event of fire. Verification of freedom from halogens ensures that the halogen content in products or materials is within statutory limits and there is no hazard for users.
Table of contents
- What are halogens?
- What does halogen-free signify?
- Methods for testing for freedom from halogens
- Freedom from halogens and the related standards
- Testing for halogen-free at Quality Analysis
- Verification of freedom from halogens and its goals
- Applications for freedom from halogens
- Summary: halogen-free
What are halogens?
Halogens are the elements in the 7th main group of the periodic system. Fluorine (F) and chlorine (Cl) are gaseous, bromine (Br) is liquid and iodine (I) and astatine (At) are solids. These elements share certain characteristics, for instance the ability to form salts. Although halogens are uncommon as pure elements in nature, they are widespread in the form of compounds, that is as part of molecules consisting of several elements. They play an important role in biological processes as well as in industrial applications. The group of halogen compounds includes the notorious greenhouse gas CFC; this gas is considered responsible for damage to the ozone layer.
What does halogen-free signify?
In practice "freedom from halogens" does not necessarily signify that a material is absolutely free of halogens, but that the concentration of halogens is below specified limits. Accordingly, materials are termed free of halogens if they do not contain halogens or only contain very small quantities of halogens. These limits are specified in various standards and directives.
For this reason, testing for freedom from halogens is important
Not all halogens are, per se, harmful. Some halogen compounds, such as fluoride in drinking water or iodine in foodstuffs, are actually important nutrients. Other halogens are used, for instance, in disinfectants and cleaning agents. However, halogenated substances can also be harmful. This is particularly the case if they enter the environment in an uncontrolled manner.
Korrosive Gase durch Verbrennung
Halogens are extremely reactive. During the combustion of materials, for example, corrosive and toxic gases may form that are harmful for the environment and health. Furthermore, halogens in electronic components such as cables can cause corrosion and degrade the performance and service life of equipment.
Freedom from halogens for certainty, environmental sustainability and reliability
There are laws and standards that stipulate the analysis of water, soil and air for halogens to protect the environment and the organisms that live in it. The determination of the halogen content is also important during the disposal of waste and quality control in various industrial sectors. For this reason, in some sectors such as the electronics, automotive and aerospace industry, there are strict requirements on the freedom from halogens. Only in this way are the safety, reliability and environmental sustainability of products ensured.
Methods for testing for freedom from halogens
Various analytical methods are used for testing for freedom from halogens, these include ion chromatography (IC), gas chromatography mass spectrometry (GC-MS) and X-ray fluorescence analysis. Particularly notable is combustion ion chromatography (CIC) with its high accuracy and precision during the measurement of halogens.
Determination of the overall levels using CIC and sum parameters
Combustion ion chromatography is based on the analysis of the overall halogen levels in a sample using sum parameters such as TOF, TF, AOX and EOX. This method provides a quick analysis and is particularly useful if the issue is to obtain an overview of the total halogen content. Here the sample is subjected to combustion in a high-temperature oven resulting in the conversion of halogen compounds into hydrogen halides. These gases are then collected in an absorption solution and analysed using ion chromatography. This method permits the precise, comprehensive quantification of the halogens, which is particularly important for compliance with environmental standards. By means of the complete combustion of the sample, all halogen compounds are acquired permitting the precise determination of the quantity of all halogens contained in the sample. At the same time, very low concentrations can be verified.
What are the sum parameters AOX and EOX?
AOX (adsorble organically bound halogens) refers to the total amount of halogenated organic compounds in a sample that can be adsorbed on activated carbon. This parameter permits the direct estimation of environmentally relevant, water-soluble contamination by halogens. This value is particularly informative for the assessment of the quality of water and waste water.
EOX (extractable organically bound halogens) is an analytical parameter that provides information about the quantity of the organically bound halogens (chlorine, bromine and iodine) in a sample that can be obtained by means of extraction. EOX is used primarily during the analysis of solids, for instance excavated soil and building rubble, as well as occasionally during the analysis of water samples.
Freedom from halogens and the related standards
Various standards and directives are of relevance for ensuring that products comply with the requirements for freedom from halogens. The RoHS directive issued by the EU specifies limits for hazardous substances in electronic and electrical devices. DIN 14582 characterises waste, DIN EN 15408 solid recovered fuels. ASTM D7359-23 describes a standard test method for the determination of halogens using CIC. DIN EN IEC 60754 (VDE 0482-754) specifies requirements and test methods for halogen-free cables and wires. IEC 61249-2-ff series specifies requirements on halogen-free printed circuit boards and limits for halogenated flame retardants. Various VDE standards such as the above-mentioned VDE 0482-754 define specific requirements for halogen-free electrical products and materials that apply in Germany and other EU countries.
Testing for halogen-free at Quality Analysis
We, as an accredited test laboratory, offer precise analytical methods for the verification of freedom from halogens of your samples and products to ensure they are safe and harmless. Here we rely on the latest standards and methods for our analysis to ensure that your samples are analysed with the highest precision and in accordance with internationally recognised standards. By providing you with exact data, we assist you with compliance with regulatory requirements, contribute to product quality and ensure your sample is harmless.
Verification of freedom from halogens and its goals
The verification of freedom from halogens is an important step for ensuring that products comply with the highest standards in relation to safety, health and the protection of the environment. The determination of the halogen content, both in raw materials and end-products, is therefore of crucial importance in various industrial processes.
The analysis of raw materials makes it possible to monitor the halogen concentrations and to ensure that they meet product quality requirements. Also important is the verification of the freedom from halogens of the end-product. Here the issue is not only the confirmation of compliance with regulations, norms and quality standards, but also the minimisation of potential risks for consumers and the environment.
Applications for freedom from halogens
In areas such as electronics manufacturing, the plastics industry and medical technology, halogen-free materials are particularly important. By ensuring freedom from halogens, the fire risk is reduced and the exposure to potentially harmful chemicals is minimised.
Electronics manufacturing
In electronics manufacturing, freedom from halogens plays a crucial role, particularly during the manufacture of cables, wires and electronic components. Halogen-free materials are preferred, because if there is a fire, they release fewer toxic gases and therefore increase the safety of personnel and installations.
Plastics industry
The increasing importance of halogen-free plastics is particularly apparent in areas with strict fire safety standards. They are used in the production of housings for electronics, furniture and construction materials. Their use not only reduces the environmental impact, it also increases fire safety.
Medical technology
Medical devices and instruments must meet very high quality and safety standards. Freedom from halogens contributes to minimising the risk of harmful emissions during use and the protection of the health of patients and medical personnel.
Summary: halogen-free
Testing for freedom from halogens is of crucial importance for ensuring that products and materials are free of harmful fluorine, chlorine, bromine, iodine and astatine compounds. These compounds are identified by means of special methods such as combustion ion chromatography (CIC). Testing for freedom from halogens is undertaken in various sectors such as electronics manufacturing, medical technology and the plastics industry to ensure the safety of consumers and the environment.
