VDMA 24364 Testing of Paint Wetting Disorder Substances (LABS Compliance)

Paint wetting impairment substances (LABS) can cause coating defects, even in very small amounts, and therefore affect coating quality. In the automotive industry, this issue applies to all paint companies. Therefore, paint plant operators control the materials and components used and set requirements for LABS-compliant products for their suppliers.

Because silicones were initially often viewed as substances that inhibited paint protection, the term silicone-free is still used incorrectly today. Whether a substance causes paint protection degradation depends on its interaction with the paint system. The LABS compatibility statement defines the requirement regardless of the substance.

The standard "VDMA 24364 Testing of paint wetting impairment substances (LABS compliance)" by the German Engineering Federation (VDMA) serves as a reference and provides an overview. Depending on where a product is used, there may be different requirements for LABS compliance. This standard defines the requirements for LABS testing, taking into account the intended use, the product's intended use, and classification into product groups.

The VDMA 24364 standard helps:

• For a quick and easy introduction to the diverse and complex subject of paint protection deterioration agents.
• For a general understanding of statements regarding LABS compliance of systems, products and components.
• In order for the test to be carried out in accordance with this standard of the VDMA.
• For possible measures for LABS compliance in production.

Paint wetting agents are ubiquitous in everyday life, resulting in regular contact with these substances. Therefore, special precautions must be taken to prevent contamination with paint wetting inhibitors.

Typical LABS resources in production include:

• Lubricants (moving parts of equipment)
• Release agents and plasticizers from plastic components used in plant engineering or workpieces
• Traces of shrinkage agents and lubricants
• Hoses and sealing compounds
• Contamination emitted via room air technology, process air technology or compressed air system
• Transported from other production areas
• Contaminated paint material, e.g. due to improper handling or storage or unsuitable additives (additives, solvents)
• Operating and auxiliary materials such as detergents, detergent cloths, abrasives, polishes, adhesive tapes, gloves, work cloths (e.g. impregnation) or assembly devices.

Typical LABS resources for individuals include:

• Cosmetics, skin care products, shampoo, hair spray, hair gel, hair dye, eyeglass cleaner, deodorant, lipstick, aftershave, make-up, skin protection lotion
• Clothing (e.g. impregnation), shoe care products
• Food and beverages (fatty acid esters such as butter, oils), drinking vessels (release agents in coffee machines)
• Plastic bracelets or jewelry, fitness trackers, smartphone cases.

The consequences of LABS contamination are:

• LABS contamination can cause coating defects in the form of craters and large-area deteriorations in the coating surface.
• LABS defects lead to product remanufacturing or rejection and, if necessary, production shutdowns.

Customers often require the absence of paint wetting impairment substances as a product feature. This formal basic requirement is not always technically feasible. For example, many plastics contain plasticizers or mold release agents that can interfere with paint protection. Such materials can never be LABS-free, but they can be LABS-compliant depending on the application or field of application. For these, testing is required on a case-by-case basis, depending on their use in LABS-critical areas.

LABS compliance refers to the condition of a material or test sample that does not cause any degradation in paint protection when tested according to VDMA 24364. Different test methods and coating systems may lead to different results.

Testing LABS compliance with the VDMA 24364 standard involves the following steps:

• The product group is selected based on the product's intended use and its zoning classification. It forms the application reference for LABS testing and thus forms the basis for selecting the test class.
• The test class should be selected based on exposure when the product is used as intended. The table provided in the standard provides examples for selecting the test class.
• The product's respective surfaces must be taken into account. These are surfaces that may release or transfer paint wetting-impairing substances into the LABS zone when the product is used as intended.
• Consciously classifying production areas for LABS compliance ensures that only LABS-compliant products are required for the relevant areas. With a sound purchasing strategy, savings can be achieved as inspection efforts and material selection impact the price of LABS-compliant products.
• All test instruments and auxiliary materials (devices, materials, and accessories such as gloves or pipettes) must be LABS-compliant to prevent falsification of test results. LABS-contaminated auxiliary materials may compromise the dye's preservation during LABS testing and therefore preclude a statement regarding the test sample's LABS compliance.
• The inspection procedure should be described in an inspection instruction. In addition to the testing procedure, the testing instruction also considers the conditions at the location where the testing is performed.
• Occupational safety requirements must be complied with.
• The DGUV 209-046 standard applies to the use of chemicals.
• The DGUV 209-046 standard applies to storage.
• DGUV 209-046 and DGUV 109-013 standards apply for paint application.
• For comparable test results, the following is recommended:
  • The same paint is always used
  • Always use the same solvent
• Hairspray, deodorant, perfume and other cosmetic products should not be used before and during the test, as their ingredients may affect the test results.
• Test samples must not be contaminated during testing and must therefore only be handled using cleaned and appropriate tools and auxiliary materials or tested gloves.
• To prevent cross-contamination between test samples, instruments and auxiliary materials should be cleaned and gloves should be changed.
• Before using other test samples, the test plate should be inspected for damage, craters, or similar defects. Defects that could lead to incorrect evaluation should be clearly marked. Test plates with obvious or extensive defects should not be used for testing.
• The test plate should be cleaned with solvent.
• The test plate must be clearly marked.
• Before performing the test, a reset test must be performed for each type of sample extraction. This test ensures that the test environment, instruments and aids, and work materials used during the test are LABS compliant.
• Provided that the tools and aids, equipment and test environment remain unchanged, this zero test can form a sufficient basis for further tests using the same type of sample extraction method.
• If zero testing is not performed, it is not possible to determine whether a “non-conformance” result is due to the product under test, the test environment or the tools and aids or work materials.
• If the painted test plate does not show any deterioration when the paint dries, the zero test is considered passed.
• If the zero test fails, at least one of the tools and aids or study materials is a source of LABS, or LABS is contaminated from the tools and aids, study materials, or test environment.
• Non-LABS-compliant aids and work materials should be identified and replaced with LABS-compliant materials. LABS sources should be eliminated from the test environment.

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, has a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the VDMA 24364 "Testing of paint wetting impairment substances (LABS compliance)" standard.