… if these are to be a medical device.
The medical compression stocking as a class I medical device is subject to strict specifications. Manufacturers must take a number of things into account: Among other things, it is essential to evaluate and clarify conformity with the Medical Device Directive/Regulation. If the product is not a custom-made device, a CE mark must also be affixed to the product. In order to be able to declare conformity, the manufacturer is responsible for maintaining technical documentation and a QM system to demonstrably meet all relevant essential requirements. Part of these requirements is the effective proof that a product fulfills all relevant safety and quality requirements and has the respective required product characteristics. Testing as neutral proof of effectiveness is therefore of crucial importance.
Who tests medical compression textiles?
As the only authorized testing body of the RAL Quality Mark Association for Medical Compression Hosiery (RAL-Gütezeichengemeinschaft Medizinische Kompressionsstrümpfe e. V.), the testing service provider Hohenstein carries out these tests in an accredited manner. This provides manufacturers with neutral proof of the effectiveness of their medical compression articles, e.g. for the treatment of venous and lymphatic disorders (varicose veins, chronic venous insufficiency, leg ulcers). Hohenstein tests, among other things, according to the specifications of RAL-GZ 387/1 (medical compression stockings) and RAL-GZ 387/2 (medical compression armsleeves).
What is tested on the stocking?
Hohenstein tests medical products according to the legally prescribed standards as well as additional optional parameters, e.g. to confirm product claims. Individual test setups are also produced at the customer’s request.
Obligatory for every compression stocking is the testing of the pressure course, which always depends on the desired effect of the textile. The pressure curve of compression garments is determined using the HOSYcan test device developed specially by Hohenstein. Close to the application, the test of the compression curve can also be carried out dynamically. In this case, the test device simulates the circumferential changes that occur as a result of movement. Other supplementary tests are aimed at possible changes in compression behavior during rest phases or the influence of overstretching (wear-out).
What else needs to be tested?
In addition to testing the compression effect, biocompatibility is a basic requirement for proving the safety requirements for the product. Here, for example, the cytotoxicity of the product can be determined within the framework of the DIN EN ISO 10993 series of standards. Compression textiles are usually worn for many hours a day and should therefore be as biocompatible as possible. By means of the test, cell damage should be excluded. This is investigated using cultured skin cells in the laboratory.
Are there any testing requirements missing?
In addition to the above-mentioned indispensable test characteristics, there are others which are listed below:
Microclimate: For inclusion in the list of aids, the microclimate between the skin and the stocking should be within a certain range. This can be measured using the Hohenstein skin model.
Harmful substances: If a compression product has been awarded the STANDARD 100 by OEKO-TEX® label, all components have been tested for harmful substances. This data can also be used, for example, in the risk analysis and is a prerequisite for the award of RAL-GZ. 387.
Odor management: If compression textiles are provided with special components that inhibit the odor of perspiration, their effectiveness can be investigated, for example, using a perspiration simulator or by subject testing.*
Fit: Body measurements are the basis for a good fit. How movement affects the dimensions is investigated using 3-D and 4-D scanners.
Antimicrobial efficacy: If the product is worn directly on the skin for a long time, it may be useful to equip it specifically against bacteria and viruses, for example. These antimicrobial properties can be tested by us for their effectiveness.*
Allergies/chemical irritations: Some substances released from textiles when worn can cause allergies or chemical irritation. Allergenic hazard potential is objectively assessed by evaluating sensitization potential.
Care properties: For hygienic reasons and also to maintain elasticity, it is necessary to wash compression textiles frequently. In order to ensure the appropriate longevity, certain quality criteria must already be observed when selecting the textile materials.
* the use of certain materials such as nanomaterials, silver additives, pharmaceuticals, etc. leads to a higher classification. Thus, affected products may become class IIa, IIb or III products according to MDR, depending on the risk – regardless of the actual intended use.
If you’ve read this far, certainly. Perhaps you weren’t aware that your product was subject to medical device requirements until now? Or you lack sufficient capacities to provide the evidence in a timely manner? Would you like to advertise your product as a medical device in the future and place it on the market? Then contact us or Hohenstein. We will be happy to accompany you together on your way through a correct conformity assessment procedure.
Link to website https://www.hohenstein.de/de/kompetenz/gesundheit/
Please note that all details and listings do not claim to be complete, are without guarantee and are for information purposes only.
Due to the rapidly changing situation in the context of the Covid 19 pandemic, changes in legal or regulatory requirements may occur at short notice, which we are unable to reflect on a daily basis.