EN 1420 Determination of Odor and Taste Assessment of Water in Pipe Systems

The European standard "EN 1420 Effect of organic substances on water intended for human consumption - Determination of odor and flavor assessment of water in pipe systems" describes a procedure for obtaining migration water to determine the odor and flavor of products made from organic materials used in pipe systems intended to come into contact with water intended for human consumption (drinking water). These products include pipes, fittings, accessories, and coatings.

This standard applies to products intended for use under a variety of conditions for the transportation, storage, and distribution of water intended for human consumption and raw water used in the production of water intended for human consumption. This standard specifies a test method consisting of a series of procedures. Use may be subject to relevant national regulations or system or product standards.

Following a defined pretreatment procedure, which in principle consists of cleaning, soaking in test water and then pre-washing, the surface of the test pieces, which are in practice exposed to drinking water, is brought into contact with the test waters.

The migration process is carried out under specified conditions as follows: test pieces are exposed to chlorinated and, if necessary, dechlorinated test water at 23°C (cold water test) for 72 hours, or to dechlorinated test water at 60°C (warm water test) or 85°C (hot water test) for 24 hours. If a warm or hot water test is required, a cold water test must also be performed. The type of test water (chlorinated or non-chlorinated), the temperature of the test water, and the number of additional migration periods are specified in product standards or national regulations. After this exposure, the migration water is evaluated by a test panel to determine the threshold odor number and threshold taste number.

For the purposes of this standard, the Threshold odor number refers to the value at which the sample diluted beyond the dilution ratio has no detectable odor. The Threshold aroma number refers to the value at which the sample diluted beyond the dilution ratio has no detectable odor.

Additional information regarding the temperature and sequence of extraction periods to be used in the test is included in the standard.

In an era where clean and safe drinking water is a fundamental human right, the materials used in water distribution systems play a critical role in maintaining quality. Organic materials, such as plastics and coatings commonly found in pipes, fittings, and auxiliary equipment, can sometimes leach substances that alter the taste or odor of water. The EN 1420 standard provides a standardized method for assessing and mitigating these risks. This standard ensures that water infrastructure across Europe and beyond not only meets hygiene standards but also provides sensuous water, free from unpleasant tastes and odors.

As urban populations grow and aging infrastructure is upgraded, standards like EN 1420 are becoming more important than ever. This standard helps manufacturers, regulators, and utilities ensure compliance with broader directives, such as the European Union's drinking water directive 98/83/EC.

EN 1420 applies specifically to organic materials that come into contact with water intended for human consumption. These include:

• Piping systems: Pipes, connections and valves for transportation and distribution.
• Storage solutions: Tanks and reservoirs.
• Auxiliary components: Fittings, pumps and protective coatings.

Because this standard covers both finished products and raw materials, it's versatile for manufacturers testing prototypes or regulators inspecting facilities. It's designed for a variety of waters, from purified drinking water to raw water used in production, under a variety of conditions, including temperature (up to 40 degrees Celsius) and pressure.

In particular, EN 1420 does not apply to materials covered by other standards, such as EN 1420 for metallic materials or non-organic substances.

The EN 1420 standard includes a systematic procedure for generating migration water, a sample that essentially simulates real-world exposure, and assessing its sensory qualities. The process consists of the following steps:

• Sample preparation: Test samples (e.g., pipe sections) are cut to standard dimensions and cleaned to remove manufacturing debris. The surface-to-volume ratio mimics actual installation conditions.
• Preparation and migration: Samples are typically filled with demineralized or chlorinated test water to meet local standards and stored under controlled conditions. Exposure times range from 24 hours (short-term testing) to 14 days (long-term simulation), with periodic water changes to create cumulative effects. Periods of heat and stagnation simulate domestic use, such as overnight storage in pipes.
• Sensory evaluation: The odor water is evaluated by a trained panel of tasters using a hedonic scale (e.g., 1-5 for odor intensity and 1-5 for flavor deviation). Thresholds are established: the odor should not exceed a score of 2 (hardly perceptible), and the flavor should remain neutral. Blind testing minimizes bias, and results are statistically analyzed for reproducibility.

In short, EN 1420 exemplifies how technical standards quietly support everyday life, transforming potential hazards into reliable measures. As climate change challenges water resources and new materials emerge, updating this standard is crucial.

Our organization, with its competent and experienced team, has been understanding the needs of its customers for years, providing them with advanced testing services, and assisting them in establishing, implementing, and improving management systems. In this context, we also provide testing services in accordance with the EN 1420 standard "Effect of organic substances on water intended for human consumption - Determination of odor and flavor assessment of water in pipe systems."