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Service Industry News Counters NPC, onBalance Offers

By Marcelle Dibrell 

The Sept. 15, 2014 issue of Service Industry News brought with it a surprising development. The members of the National Plasterer’s Council issued a formal invitation to the members of the consulting group onBalance, asking onBalance to teach them how it’s done. 

After years of research conducted on numerous test pools, the National Plasterers Council has apparently thrown up its collective hands, having lost its faith in plaster’s ability to withstand aggressive water’s tendency to cause spotting. 

Meanwhile, the consulting group onBalance has retained its faith in plaster, believing that a properly formulated and troweled surface won’t succumb to spotting.

Despite this confidence, onBalance has responded to the NPC’s invitation with an invitation of its own. Prior to future research, the group proposes a meeting to discuss the science on both sides. 

In this special issue of Service Industry News, we would like to issue the following compromise invitation to the members of both the National Plasterers Council as well as onBalance. 

We offer our newspaper as a platform for both parties. To the NPC, we would like to offer our staff as your investigative partners in your new test studies. We will come poolside and deliver to the industry what is discovered as its discovered. We promise to bring our smartest writers. 

To onBalance, we offer to help explain the studies that have yet to be fully explained by the press. There are meaningful conclusions that already exist from studies performed by both onBalance and the NPC, and we hope to deliver the methods and conclusions. 

In both offers, the difference between what we offer, and what has been done in the past, is that while the news has reported, the news has never interfered. As a qualified newspaper, we wish to interfere. Enough is enough!

To begin, we would like to explore the topic of spot alteration exclusively, so as not to muddy the waters with confusing interrelations. We want to be there every step of the way to document both the prior concerns, and the future results that will ultimately create new industry standards. If onBalance refuses to come to the table on this, we hope to continue to move forward, nonetheless.

At issue here is the problem of spot alteration, or spot etching, as most of the industry refers to the phenomenon. 

Appearing as white spots on a grayed background, it is an unsightly defect that occurs in both brand new and aged plaster, and has been a source of controversy within the industry for more than 30 years. 

The question? Why does it happen?

The answer? It depends on whom you’re talking to. 

The NPC explains that spot etching is a process where concentrated areas of soluble materials etch away when exposed to aggressive water. Further, these concentrated areas of soluble materials occur naturally as the plaster cures and hydrates. 

The NPC's position is that it is a phenomenon that is just about inevitable when the conditions are right. It gives you to understand that plasterers can cause spot etching to any pool by creating just those conditions. 

According to onBalance, spot alteration is actually local soft spots, or areas of porosity that occur as the result of improper troweling techniques, the use of calcium chloride in the cement mix, and varying water to cement ratios. 

Specifically, calcium chloride is a hardening agent that is known to accelerate the hydration rate of some of cement’s components, while retarding others. Meanwhile, the improper troweling techniques disturb the aggregate and then the added water penetrates around the aggregate. 

onBalance has arrived at this theory concerning the formation of spot alteration via a combination of sources. One source is the Portland Cement Association Manual, Concrete Inspection Procedures. 

This reference clearly describes the causes of concrete color variation, and attributes those causes to the use of calcium chloride, hard troweled surfaces, and surface variations in the water-to-cement ratio, among other factors. 

In support of this theory, onBalance has relied heavily on forensic evidence, such as core sampling of affected plaster, and plaster composition analysis by Ph.D. petrographers.

But while onBalance has been busy in its labs, the National Plasterers Council has been working on its own. 

In addition to other testing facilities, the NPC sponsored the construction of the National Pool Industry Research Center at California Polytechnic State University, San Luis Obispo.

After almost 10 years of research conducted by Ph.D. scientists, the NPC felt that it could confidently announce to the world that the spots are caused by aggressive water chemistry.

But years of haranguing by onBalance and others who have questioned the NPC’s performance standards may have gotten under the NPC’s skin.

It appears that the NPC has actually invited onBalance to take the trowels from their hands, and plaster a pool such that it does not succumb to spot alteration in an aggressive environment. 

“We are investigating to find out the proper way to plaster in order to avoid spot etching. It would be our hope that from this experiment, we could come out of it with all of
the recipe required to create a standard by which we can all agree that this is the way to do it,” NPC President Jeff Henderson said.

It is probable that most of the industry supports this proposal as the most responsible thing to do. If conducted properly, it would put an effective end to the controversy. 

“To create industry standards, we need to get out of the drawing room, and get away from the lecterns and the microphones and get back in front of cement holes in the ground,” Henderson said.

Of course, onBalance would argue that it has never been in the drawing room.

For decades, onBalance has pleaded with the NPC to justify its conclusions about spotting, and numerous other types of plaster defects. 

To date, it has never received much of a response. In the Oct. 15 issue of Service Industry News, onBalance gave the NPC a qualified yes. 

“We are certainly willing to undertake additional future research, but only after a careful discussion and analysis of what is already out there,” onBalance said.

Clearly, the NPC believes strongly that this issue should be resolved, and may in fact proceed with or without onBalance’s help. After all, the members of onBalance are not the only people on the service side of the problem who can question the NPC’s methods and conclusions. 

Nonetheless, we feel that it is important that onBalance participate in the experiments, because it has been the loudest voice in the industry to profess to know plastering best practices, and it is likely that without onBalance’s participation, future doubts will be cast. 

We understand that onBalance is reluctant to join hands with an entity with whom they are fundamentally skeptical. 

To that end, we hope to reveal exactly what we can conclude from the NPC’s past experiments. 

It is likely that many in the industry will see its reluctance as a lack of legitimacy: onBalance doesn’t have the science to back its claims, they could say. 

But with all that has happened in the past, the show up or shut up mentality isn’t really fair. We hope that onBalance will come to the table on this; they are a unique force that has long claimed the answer to the plaster issue, and the industry would like to see them prove it. 

The NPC’s standing position concerning spot etching is a position that hurts the service professional. It is a position that hurts his reputation, and it also hurts his wallet. 

That’s fine if the NPC is correct, but if it is not, it is grossly unfair.

Before anything else, Service Industry News is a publication for service professionals, and our agenda is to both promote science and to protect the thousands of readers for whom we write. 

Our readers are on the front lines. We aim to find answers.

Paid subscribers have full access to the complete coverage on issues of interest to the pool and spa service community. Contact our circulation department at 949-916-0292 or email for details.

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