Requirements for PTFE hoses in the pharmaceutical, food and chemical industry

Pressure test certificate:

Per the Pressure Equipment Directive (PED) all pressure equipment, including hoses, must be tested. The hose is subjected to 1.5 x the operating pressure by means of water or another medium. The data is recorded in the test certificate, which is a mandatory part of the product documentation.
―› The test certificate for hoses, chapter “Test Certificate per DIN EN 10204 3.1 – Pressure Test” confirms successful pressure testing.

Conductivity test:

Electrical conductivity is often an important property of hoses. The resistance of the hose is tested to determine its conductivity, and the results recorded in the test certificate.
―› The test certificate for hoses, chapter “Test Certificate per DIN EN 10204 3.1 – Conductivity” confirms that the results of conductivity testing were within the specified tolerances.

FDA conformity:

The US FDA (Food and Drug Administration) is the regulatory agency responsible for monitoring all goods brought onto the US market. This covers all imports, for which reason the directives and decisions of this agency are also important for manufacturers from other countries. They are binding for exports to the USA, since not every product approved for use in Germany or the EU is automatically FDA-compliant. Product manufactures therefore increasingly follow FDA standards, in order to compete in international business. FDA conformity requires materials with high durability that release no substances into foods. The food industry uses many plastics with very different characteristics, that come into contact with foods. Hoses are used in food manufacture primarily to transport liquids and pastes. Of most importance in this context is the chemical resistance of the material to substances in foods like fatty acids or fats. Furthermore, food industry hoses must have smooth interior surfaces, so that they can be cleaned readily and to prevent bacterial contamination.

The FDA regulations are divided into several sections or titles. FDA21 stands for Food and Drugs, CFR stands for Code of Federal Regulations and Part 177 for Indirect Food Additives: Polymers. This section of the FDA regulations describes the permissible polymers.
―› The certificate of conformity confirms that only FDA-approved polymers are used in the liner of the hose.

USP Class VI:

Plastics used in medical technology and pharmaceutics are divided into six biocompatibility classes in United States Pharmacopeia (USP), the US medications handbook. To assign elastomers and other polymer materials to a class, they are subjected to various tests in order to determine their biological reactivity in living organisms. The main goal of the USP is to maintain and improve human health. It is intended, by means of binding directives for the manufacture of medications and medical products, to ensure the quality of the substances inspected. This heightens the safety of patients and consumers. It evaluates the correct identity of the medication, active ingredient strength, quality, purity and composition. The standards are used by manufacturers as well as regulatory authorities. Prescription as well as non-prescription medications must meet USP-NF standards by US Federal law. In order to gain USP Class VI status, the material itself and its various extracts are subjected to the following tests in external laboratories.These tests can be divided into the following three test areas:

• Acute systemic toxicity: Determination of acute irritation from skin contact, inhalation and swallowing.
• Intracutaneous reactivity: The test material is brought into direct contact with the tissue for which its normal use is intended.
• Implantation test: The reaction after implantation in the tissue of a living organism is investigated. The duration is five days, as a rule.

Testing is done with defined exposure times and at defined temperatures, in order to ensure comparability of the results. Although biocompatibility testing must be done with the finished medical product, for the manufacturer it is important that all materials used to make the product are tested, and meet the requirements of the finished product.

USP Class VI is further subdivided in detail per EP 3.1.9. This subcategory calls for specific tests of silicone elastomers, such as the residual peroxide content.
―› USP Class VI certification confirms that the hose body material has successfully passed testing per USP Class VI.

European regulation 1935/2004:

The basic requirements for materials and objects intended for contact with foods (as defined by the LFGB1) are laid down in framework regulation (EU) No. 1935/2004. All food contact materials must meet these general requirements. Thus: “Materials and articles, including active and intelligent materials and articles, shall be manufactured in compliance with good manufacturing practice so that, under normal or foreseeable conditions of use, they do not transfer their constituents to food in quantities which could endanger human health; or bring about an unacceptable change in the composition of the food; or bring about a deterioration in the organoleptic characteristics thereof.” (Article 3 of regulation (EU) No. 1935/2004).
―› EU 1935/2004 confirms that the hose material meets the requirements of 1935/2004 for use with foods.

BfR XV. Silicone:

The EU directives are based, among other things, on the recommendations of the German Federal Institute for Risk Assessment (BfR). This results in further-reaching equirements for materials such as silicone (BfR XV.Silicone). Here, specific requirements for starting materials like silicones are set forth.
―› This requirement/rule applies only when silicone is used in the hose.

3-A Sanitary Standard:

3-A Sanitary Standards Inc. (3-A SSI) is an independent, non-profit organization in the US whose purpose is to improve hygiene design in the food, beverage and pharmaceutical industries. The 3-A symbol is administered by 3-A SSI and is a registered mark that identifies operating materials that meet 3-A Sanitary Standards. These standards are defined for the design, manufacture and cleanability of daily food equipment. They come into force when such equipment is used in the handling, production and packaging of consumable products with high hygienic requirements. These hygiene standards are the result of joint efforts by industry experts, production system manufacturers, food and beverage producers and hygiene regulatory authorities. The goal of 3-A SSI is to protect edible or drinkable consumer goods from contamination, enable mechanical cleaning of all product surfaces and simple disassembly for manual cleaning. 3-A standards are recognized and accepted worldwide.
―› The implementation of hygiene standards for food use is confirmed.

ISO 10993:

ISO 10993 describes the most important test procedures for the biological evaluation of the cytotoxicity of medical products. Cytotoxicity is the ability of a substance to damage or destroy a living cell.
―› ISO 10993 confirmation certifies performance of the test procedures described in the standard.