EN 248 Sanitary Fittings - General Specifications for Ni-Cr Electroplating Coatings

The purpose of the European standard “EN 248 Sanitary fittings - General specifications for Ni-Cr electroplating coatings” is as follows:

• Describing the condition of the exposed surfaces of faucets.
• To determine the properties of the surface coating (corrosion resistance, adhesion).
• To describe the tests that will be conducted to verify these features.

This standard applies to all sanitary fittings (supply or waste fittings) with a metallic Ni-Cr coating, regardless of the substrate material.

In the world of plumbing and sanitary ware, durability, aesthetics, and safety are paramount. Homeowners, architects, and manufacturers rely on standards to ensure that everyday fixtures like faucets and valves function reliably over time. One of these critical standards is EN 248, which specifies the requirements for electroplating nickel-chromium (Ni-Cr) coatings on sanitary fixtures. This standard guarantees that these coatings provide corrosion resistance, wear protection, and a high-gloss finish that can withstand the rigors of daily use in bathrooms, kitchens, and public facilities.

The EN 248 standard remains a fundamental element for the sanitary fittings industry today. By harmonizing fitting specifications, covering both inlet and outlet components, it helps manufacturers comply with regulatory requirements and consumer expectations.

The EN 248 standard applies to all sanitary fittings with a metallic Ni-Cr coating. This coating is a layered electroplating process where nickel serves as a base for a harder chrome top coat. This combination provides a bright and reflective surface that is not only visually appealing but also functional.

The standard's scope is precise: it covers surface properties, thickness requirements, adhesion tests, and corrosion resistance assessments. It does not define the faucet's design, but focuses on coating quality to prevent issues such as pitting, peeling, or discoloration that could compromise hygiene or longevity. In high-traffic environments, such as hotels or hospitals, compliance with the EN 248 standard minimizes maintenance costs and the risk of bacterial growth. Key considerations include:

• Coating thickness: The minimum requirements necessary to ensure durability are typically measured in micrometers (μm) for both nickel and chromium layers.
• Appearance: Free from defects such as cracks or bubbles, and homogeneous.
• Performance tests: Including adhesion and abrasion resistance through salt spray exposure and bending tests.

Nickel-chromium plating has been a fundamental application in the industry since the early 20th century, evolving from decorative coatings to essential protective layers. In plumbing applications where water flow, moisture, and cleaning agents are constant, untreated metals corrode rapidly. Ni-Cr coatings solve this problem in the following way:

• Provides corrosion resistance: Chromium forms a passive oxide layer that protects against rust and chemical attacks.
• Enhances aesthetics: The mirror-like coating resists fingerprints and water stains, providing a premium look.
• Increases durability: Nickel substrates balance mechanical stress, preventing cracks in brittle chrome.

Without EN 248 and similar standards, variations in coating quality can lead to premature failures. This standard prevents the faucet from losing functionality after a year by implementing rigorous testing. With the increasing emphasis on sustainable production in recent years, these coatings also support recyclability, as chrome-plated components are easier to renew rather than replace.

The EN 248 standard includes specific properties of Ni-Cr coatings, highlighting two main elements:

• Condition and corrosion resistance of exposed surfaces.
• Performance characteristics such as coating adhesion.

In terms of surface condition,

• Coatings must be smooth and even, and free from defects such as pits, cracks, bubbles, or pores.
• The final coat should have the bright and reflective appearance characteristic of high-quality chrome plating.
• Minimum thickness requirements vary according to the coating class (e.g., Class 1 for decorative purposes requires a minimum of 0,3 microns of chromium over nickel layers).

In terms of corrosion resistance,

• Neutral salt spray test: Samples are exposed to 5% sodium chloride vapor for up to 96 hours, depending on the class. Corrosion spots larger than 1 mm in diameter are not permitted on the coated surface.
• Sulfur dioxide test: In more challenging environments, exposure to sulfur dioxide-laden moisture simulates acidic conditions, ensuring you are not exposed to the base metal after 8 hours.

These tests simulate real-world exposure to chlorinated water, detergents, and atmospheric pollutants.

In terms of adhesion and durability,

• Bending test: The coated faucet is bent 180 degrees around a mandrel; the coating should not peel or flake off.
• Adhesive tape test: Apply and remove the adhesive tape; none of the coating should separate.
• Abrasion resistance: Although not directly stated, it is linked to relevant tests regarding standard scratch resistance.

Verification is not optional; the EN 248 standard mandates a series of laboratory tests to confirm compliance.

• Visual inspection: For aesthetic homogeneity.
• Thickness measurement: Using magnetic induction or beta backscattering methods.
• Corrosion exposure: Salt spraying is carried out in controlled chambers according to the ISO 9227 standard.
• Adhesion checks: Mechanical stress tests to simulate handling and assembly.

Samples are pre-conditioned (e.g., boiled or heated) to accelerate aging. Failure in any test disqualifies the batch, allowing only sound products to reach the market. Manufacturers must document these results.

In conclusion, the EN 248 standard is a cornerstone of quality in sanitary fittings, blending aesthetics with performance. By specifying electroplated Ni-Cr coatings that resist corrosion and wear, it protects both user satisfaction and product lifespan.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its customers, providing the advanced testing services they require, and assisting in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services to businesses in accordance with the "EN 248 Sanitary fittings - General specifications for Ni-Cr electroplating coatings" standard.