Holiday Testing: What It Is and Why It’s Needed

By: Rob Burckley, Induron Sales Representative

Holiday Testing Protective CoatingsThe holiday season is a time of joy, celebration, and quality time with loved ones. However, for those in industries dealing with protective coatings, it’s also a time to ensure that the shield guarding against corrosion and deterioration remains intact. Holiday testing, in this context, isn’t about festive decorations but rather a crucial process in maintaining the integrity of protective coatings. 

What is Holiday Testing?

Holiday testing is a quality control technique used to detect discontinuities (such as pinholes or voids) in protective coatings. The testing standard NACE SPO188 is for testing newly-applied coatings to a conductive substrate. The test will determine if there are enough coatings to resist the electrical charge, which will determine if there are any pinholes or voids in the protective film.

This test will be either low voltage or high voltage based on coating thickness. Low voltage testing is recommended for coatings thicknesses below 20 mils DFT, while High voltage testing is recommended for coatings thicknesses up to 1” thick (1,000 mils DFT!).

Testing coatings less than 20 mils will be done with a low voltage tester. This will use a wet sponge, surfactant and a connection to the substrate to complete the circuit. If the sponge detects a flaw it will “jeep” and alert the inspector. Then, he or she will mark the area for repair.

Testing coatings greater than 20 mils will be done with a high voltage tester. It’s essential to set the tester to the correct voltage to avoid damaging the coating and for safety reasons. This device is connected to the substrate and uses one of several different types of electrodes (brass brush, steel brush, etc). The type of electrodes depends on the substrate. Typically, voltage testers are set to 125 volts/mils. It’s always best to check with the coatings manufacturer. 

Why is Holiday Testing Needed?

Holiday testing is a vital procedure that helps pinpoint potential weak spots in the protective layer, ensuring that any vulnerabilities are addressed before they escalate into more significant issues.If either thickness or the presence of voids is left after a coatings application, then the coatings will not perform correctly and long term protection of the owners assets will not have been achieved.  

Here are 4 reasons for holiday testing: 

  1. Corrosion Prevention: Protective coatings act as a barrier between the underlying substrate and corrosive elements in the environment. Even a small breach in this barrier can expose the substrate to corrosive agents, leading to rust, decay, and structural damage. Holiday testing helps identify and rectify these breaches before they compromise the coating’s effectiveness.
  2. Cost Savings: Addressing coating issues early through holiday testing can significantly reduce the long-term costs associated with maintenance and repairs. Identifying and repairing discontinuities promptly prevents the need for extensive re-coating or even replacement of entire structures, saving both time and money.
  3. Compliance and Safety: In many industries, compliance with specific coating standards and regulations is mandatory. Holiday testing ensures that protective coatings meet these standards, guaranteeing the safety and environmental integrity of the structures they shield. Non-compliance can lead to regulatory fines and pose safety risks.
  4. Longevity of Assets: Protective coatings are an investment in the longevity of assets. Holiday testing is a proactive approach to asset management, extending the life of structures and equipment by addressing coating issues early on. This is particularly crucial for critical infrastructure where the consequences of failure can be severe.

Holiday testing for protective coatings may not be the most festive of activities, but it plays a vital role in ensuring the continued effectiveness of these coatings. As industries continue to advance, the demand for reliable and durable protective coatings grows. By incorporating holiday testing into routine maintenance practices, industries can uphold the integrity of their assets, safeguard against corrosion, and enjoy the holiday season without the worry of unforeseen coating failures. After all, a little preventive care during the holidays can go a long way in preserving the gifts that protective coatings bring year-round.

Leave a Reply