Seeking Standardization in Coating Specifications for Wastewater Projects

By: Andy Odorzynski, Induron Sales Representative

This article was originally published in the September 2017 issue of the Journal of Protective Coatings & Linings.

As a technical sales representative for a paint manufacturing firm, I have the opportunity to work with specifying engineers and facility owners of projects spanning many different industries. Few industries present the same level of challenges in coatings specification development that one encounters in the wastewater marketplace. Outside of a few firms with industry expertise, specifying engineers tend to rely entirely on paint manufacturers to select coatings for their wastewater specifications. This has created an environment where specifications vary wildly. This article will discuss how we as coatings professionals can better support the specifying engineers with whom we work to bring about some consistency and guidance to the development of wastewater specifications.


Differences in equipment. influent sources and operating practices can create very different service exposures from one wastewater plant to the next. Understanding these factors on a case-by-case basis is a necessary requirement of authoring a coating specification that will require long-term performance without unnecessarily increasing the cost and complexity of a project. Yet, consideration of these factors is rarely the driving force for which coatings are listed in a specification. Many current specifications began as sole-sourced documents where there was no motivation for the coatings sales representative to pursue value. This can result in multiple negative outputs including the following:

  • Coatings can be over-specified. For example, I have seen 4o-plus mils of high-performance epoxy (i.e., novolac or glass-flake reinforced) required in secondary clarifiers where the service exposure is relatively benign and is often comparable to that of a potable water tank, where B-to-q0 mils of a standard workhorse polyamide epoxy is considered adequate. The cost of using these unnecessarily robust materials is higher than alternatives that would have been perfectly adequate for the exposure. lt can also result in the requirement of multiple coats to achieve the required film build, the use of plural-component equipment, additional environmental controls and other measures that increase cost and complexity. Had the coatings been appropriately matched to the service exposure, these additional costs could have been avoided.
  • Coatings can be under-specified. Wastewater headworks (the initial stage) will include exposure to H2S and H2S gas. In some specifications, coatings are listed that were never designed to tolerate this sort of environment and will result in premature failure.
  • Service environments are not properly classified. The current practice for most specifications is simply to lump together large categories such as “H2Sexposed immersion steel.” This practice insufficiently addresses the difference in potential exposure from one piece of infrastructure, which technically meets this definition, to the next. Rather, each piece of infrastructure must be evaluated for its specific expected service environment. With this approach, specifications can be written accurately for more benign environments without giving up the robust protection necessary in others.

Identifying the right surface preparation, coating system and thickness is not a science that results in only one answer. There is likely to be a range of options which are all appropriate in terms of performance, cost and complexity for any given environment. To some extent, it is simply a judgment call for a specifying engineer. This diverse range of options is, by and large, a positive thing but unfortunately, it can also be very confusing to navigate.

The commercial interests of coating manufacturers can further complicate the matter. As sole-sourced specifications have diminished, those coatings manufacturers who are added to existing specifications may simply choose to list their equivalent products without re-evaluating the logic of what was previously listed. They may also choose to look for areas where they know they have a specific pricing advantage and write in products that make it more likely for their company to be selected by a contractor, even if they know they are sacrificing performance and long-term value. Though the vast majority of technical and sales representatives in the industry are honest and well-intentioned, sales goals and the pressure to win are very real forces. These business realities simply create an inherent conflict when coatings manufacturers are authoring specifications.

Other problems with this practice come into play as well. Not all coating manufacturers have product lines complete enough to deal with the panoply of requirements encountered in a wastewater plant. lt’s never good when a company is simply listing what they have and not necessarily what’s required. Another factor worthy of consideration is that many individuals who are placed in the position of supporting specifying engineers on behalf of a coating manufacturer have no real training or expertise that affords them the knowledge required to effectively offer that support. They are simply doing their best, but this can lead to a lot of “copy and paste” specifying rather than project-by-project analysis.

In a perfect world, the specifying engineer would understand the details of protective coatings and the requirements of the project well enough to police these issues. Indeed, there are great engineering firms throughout the country who do exactly that. Unfortunately, they are more the exception than the rule. Most often, an engineer is working from a document handed to him or her by a superior that they may be reluctant to change. To summarize concisely, there is a real need to offer guidance on wastewater specification development to both the community of coating sales and technical representatives, as well as specifying engineers.


The problems detailed here are not unique to the wastewater industry. The same list of concerns and need for standardization in the potable water storage industry led to the formation of the American Water Works Association (AWWA) D102, “Coating Steel Water-Storage Tanks.” This standard is what’s known as an industry consensus, voluntary, minimum standard. Here’s what that means.

Industry Consensus: This standard is developed by a team of coating manufacturers, application contractors, facility owners and other at-large members. The qualifications of each member of the team can be evaluated to ensure that they have requisite experience and expertise to inform and contribute to the process. These individuals are heavily involved at the front lines of the projects that they seek to guide. They understand what is confusing people, what is causing conflict and who needs their help. They work as a team to set aside competitive interests and identify and articulate the best methods to resolve conflict and provide guidance.

Voluntary: This standard is not legally required in the manner OSHA and other legislated standards and building codes would be. Specifying engineers have the option, not the obligation, to include the standard on projects where they see fit to do so. This is an important attribute because it tends to cull standards that are not useful from the herd. lf the document is effective in its mission and adds clarity and value, it will gain widespread adoption and remain relevant. lf not, engineers will simply not include it on their projects. This greatly limits the risk of creating undue burdens for those attempting to plan and execute projects which fall within the scope of the standard.

Minimum Standard: The document represents only the minimum requirements. lf for any reason, an engineer should choose to specify more robust products or more stringent requirements, he or she is free to do so. In this manner, the document never encumbers a specifying engineer’s ability to design a project as they see fit. Rather, it helps to ensure that all projects meet at least a minimum level of constraints. lt seeks to set a floor for quality and allow a clear designation when one is moving beyond the minimum acceptable requirements to voluntarily take additional measures. These standards also offer a logical location to place appendices that are not technically part of the standard’s requirements. Commentary on factors to be considered, recommended practices, additional references and more can be included to provide consistent insight and guidance. The industry experts who work together to author the standard can use this as a forum to communicate many items that should be taken into account during project design. When properly to executed, this results in a document that can provide enormous value and guidance for everyone involved in the coating process from design to execution.

As an example, consider the comparison to AWWA D102, which deals exclusively with one product: potable water. In contrast, a wastewater treatment facility can have influent, which results in wildly different service requirements if they include industrial by-products. Such a standard would have to assume certain service exposures for the systems it proposes in each environment. These assumptions must be explained to the user of the standard. As a minimum requirement, there may be many instances where testing is necessary to determine whether or not the systems contemplated are sufficient. Commentary included in appendices allows the explanation of these factors, the relevant metrics for which one would test. and the use of that data.

The time has come for a similar standardization effort in the wastewater treatment industry. The development of industry consensus, voluntary, minimum standards would set up a third-party point of reference for engineers looking to ensure that they have a well-designed project, but not an over-designed project.


While it is easy to see the benefits that such a standard would offer, there are good reasons why one does not yet exist. First and foremost, among them is the sheer scope of the undertaking. lt would be a large and challenging operation simply to write a standard for digesters. Some structures are concrete, and others are steel. Some are aboveground, and some are buried. The differences in state and local legislation will affect which options are even available to choose from on one project to the next. To truly deliver on its purpose, a standard would have to deal with all of these issues and would have to do so for each piece of infrastructure covered by the standard—truly a massive pursuit.

Starting from blank paper and developing standards from scratch is extremely difficult. Right out of the gate, the would-be committee members would have to make some tough decisions about the scope of the endeavor. ls the industry better served by writing one large standard or multiple smaller standards on a per-structure basis (such as for grit pumps, digesters and clarifiers)?

Because such a standard would be developed by a committee, even a dedicated and hardworking group would take years to publish a useable document. lf the committee were to overextend itself by attempting to capture too much infrastructure in one document, it would run the risk of being out-of-date before it was even published. Further, these standards must be maintained and updated on a regular basis in order to stay current with changes in coating technology, legislative requirements and industry standard practices. For this reason, it may prove that such an effort would have to be tackled by multiple committees focused on different portions of vital infrastructure.

Another question of scope is which pieces of wastewater infrastructure should be covered by a standard or standards. lt would seem a misstep to attempt to address all coating requirements within a wastewater treatment facility. For example, while many wastewater specifications contemplate coating CMU (concrete masonry unit) walts, it would be a waste of a committee’s time to develop a standard around these activities. This begs the question, “where is the line?” What do you include and what do you leave out?

I would submit that one can limit the scope of the proposed standard(s) by weighting the ubiquity of the structures by the expected severity of their environments. For example, the headworks of a wastewater treatment facility is likely to include equalization tanks and influent channels, which require protective coatings in all treatment plants. Therefore, we have high ubiquity. Because these pieces of infrastructure are exposed to raw, untreated influent they tend to be extremely corrosive environments. This combination would place them high on the list of items to be covered by a standard. lt’s also important to remember that we have to start somewhere. A committee could publish an effective standard with a limited scope and append it over time. This would still add value to the community, even if there is more work to do in the future to increase that value.

The lack of consistency in recommendations across coating manufacturers reflected in existing specifications can also be seen as evidence of the lack of consensus that exists inside the industry. lt would be no small feat of politics to get a room full of owners, engineers, contractors and paint companies to agree on an appropriate minimum standard. Yet, it’s been done before in other industries. The ability to list multiple options as acceptable for a given service environment allows a standard the freedom to represent multiple approaches.


While these challenges are real and daunting, they are surmountable. Having had the pleasure of working with professionals throughout the industry on standards committees, I have seen firsthand their ability to work toward what’s best for the industry as a whole. The time has come for us to begin the formation of a committee to start discussing the scope and execution of wastewater treatment standards for coatings and linings. This committee will need knowledgeable, hardworking individuals who are dedicated to improving the issues detailed in this article.

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