Healthy Air, Healthy Water
Best Practices to Keep Patrons & Staff Healthy
There is no more critical issue to municipal or private pool owners than the safety of their swimmers and staff. Failure to maintain safe water and air quality can lead to health issues and a poor user experience. Swimmers not only won't come back—they might also let others know not to go to your facility. Such a situation "would create an economic impact, as well as a reputation impact, which would be hard to overcome," said Peter Beireis, senior recreation supervisor, City of Newark, Calif.
The key to ensuring good air and water quality is reducing contaminants in the water, he said.
Characteristic of most indoor pool areas is that "pool smell," which is due, not to chlorine, as most people think, but to chloramines. According to the Centers for Disease Control and Prevention (CDC), chloramines form when the chlorine used in pools to kill germs binds with the body waste that swimmers bring into pools, such as sweat and urine. Chloramines in the water can irritate skin, eyes and the respiratory tract as they off-gas into the air, particularly indoors. They also can contribute to corrosion of metals around the pool and in the facility's air handling systems.
"Please note that just about all indoor facilities will have chloramines and somewhat of a smell," Beireis said. "It is an ongoing issue, a dilemma, as you are fighting chloramines from the incoming water source, and then once your bathers enter they are creating more from the contaminants, such as sweat, that they bring into the water. Your chlorine is working hard to deal with it, but the end result is the chloramines."
Diligent monitoring of your water chemistry, therefore, is imperative, Beireis said. "If you stay on top of things, you will notice what is happening with your chloramines. Then you can super-chlorinate the water to break the chemical bond of the offensive nitrates."
Although prevention is the best option, added Thomas M. Lachocki, CEO, National Swimming Pool Foundation & Genesis, of Colorado Springs, Colo., the public pool world is moving to other techniques to improve water quality. Disinfection and filtration have been used for a century. Most new facilities are also using supplementary disinfectant like UV or ozone.
"For indoor pools," Lachocki said, "advances in air handling are an important way to remove volatile contaminants from the pool environment. For smaller—high-risk—bodies of water, controllers and automatic feeders are a must."
Best Practices: Water Balance
To maintain healthy water for swimmers, the number one concern is always going to be proper balance of the water, according to Terry Arko, water specialist with a Norwalk, Conn.-based chemical manufacturing company that specializes in swimming pool and spa care. "Balance can depend on regional situations, primarily when getting water into the pool itself," he added. "Source water plays a big part there because in some areas of the country you have very soft water, which can lead to corrosion, while in other locations you have hard water, calcium-rich, which can lead to scaling of equipment." This scaling leads to higher energy, operating and maintenance costs.
Pool operators know there are standards that define proper pH balance, calcium hardness and more. "Water balance is the top concern overall." Arko said. "Then there is the proper use of sanitizers. One thing that can happen, particularly in busy municipal facilities, is that operators will tend to go high on their chlorine to deal with higher bather/swimmer loads, which can lead to more chloramines. Proper sanitation, understanding the proper levels, maintaining proper levels, is really important."
A sometimes-overlooked aspect of maintaining water quality is understanding the proper swimmer limits in the pool, Arko noted. "Pools can get overwhelmed because operators allow too many people in the water at one time," he said. "That's a tough one to deal with, but understanding how many bodies a pool can accommodate before it becomes overwhelmed is important. Code standards vary, depending on your state's health department, but the basic standard is to allow 20 square feet of pool surface per bather. What that means is, for example, if you have a 30-by-50-foot pool, that is 1,500 square feet of surface area. Divide that by 20. So, in a 30-by-50-foot pool, your maximum bather load is 75 people."
"The biggest thing I've noticed," said John Watt, product development specialist, with a Minneapolis-based company specializing in water quality and management systems, "is that many facilities are not managed properly. A service company comes in a few times a week as opposed to making daily or hourly checks. We are seeing where the pH goes up because no one checks the level for two or three days, so it is difficult to stabilize the pool. The best practice in keeping water quality up is consistent checks on the water chemistry itself based on water temperature and location of the pool."
Record-keeping is important, Watt said. "The only way to build consistency is to keep a record of what is added to the pool. Do a complete chemistry check—not just pH and chlorine levels."
Operators would also be well advised to put together a preventive maintenance plan in place for all equipment and stick to it, added Brian Bokowy, business manager, of a Gainesville, Fla.-based supplier of bulk chemicals for the swimming pool industry. "Schedule maintenance at a time to minimize the impact on your patrons and budget accordingly for it annually," he added. "Thoroughly understand what tasks your staff is capable of performing themselves and when you need to rely upon a service company or contractor. Pay particular attention to the filtration and circulation components of the system like the pumps and filters. These components are the fundamental building blocks that everything else relies upon."
Best Practices: Air Quality
Any discussion of air quality in an indoor pool facility begins with building design, and having the proper air flow devices, such a dehumidifiers. "When you think about it," said Arko, "a pool is somewhat of an engineering feat because you are taking equipment, materials, plasters, concrete, and putting thousands upon thousands of water into that. All of this is subject to corrosion, subject to hydrolysis, and subject to dissolution from the water and the chemical mix."
Then, you enclose the pool in a building, in a vacuum, and have to deal with factors like humidity control, proper ventilation and how the air is going to be distributed properly.
Older indoor facilities face a challenge, if they are recirculating the air on the inside of the facility but not pulling that frigid air from outside. "They are running the same air back through the system," Arko said. "They are pulling the humidity out of the air with the dehumidifier, but they are not improving the air quality."
There are air circulation regulations, explained Jason Mart, president, of an Indianapolis-based commercial pool renovation and construction company, "but until recently there really hasn't been much attention paid to how the pool's disinfectant byproducts, and chloramines can be removed from the structure. The traditional approach has been to take the chloramines and disinfectants—all those 'yucky' gases—and diffuse them by bringing in a lot of outside air. But you are really not getting rid of them. And so what I suggest with the bad air is to sweep it out of the building."
That, too, can pose challenges in older facilities. Air handling systems, because of design constraints 30 years ago, are typically undersized relative to their cousins in facilities being built today, said Richard Deakin, an expert in product development with a London, (Ontario), Canada pool manufacturing company. "Today," he said, "you'd see a completely different air handling system. A majority of our approaches in these older facilities serve as Band-Aids at best until facility owners address the air-handling process in the equation. Because if we are not removing that material, regardless of the amount that we reduce effectively from that environment, we're back in the same boat."
Yes, in older facilities that is a huge problem, Arko agreed: "the design of the air flow, the air ducts, understanding evaporation rates, temperatures in the facility, and again the pool chemistry." He added, "When talking about humidity, you want a good dehumidifier in the building, something that is going to maintain about a 50 to 60 percent relative humidity. High humidity is bad. That is bad for the building, the structure, and is going to be uncomfortable to your patrons. It can create mold and mildew problems."
The NSPF recommends about six to eight air changes per hour in a pool facility. If there is mechanical cooling of the building that will be four to six air changes per hour.
Proper movement of air across the water is also key because of potential chloramine buildup that tends to settle at the surface of the pool—exactly where people are swimming and breathing. You want to ensure that those gases are being broken up, and moved by good air circulation close to the water level.
The Influence of Technology
There are a number of technologies that will help in the battle against chloramines. UV is one of them. "It will not eliminate the problem entirely," Beireis said, "so when you get to a point of super-chlorinating, then you need to rely on your air handling system."
In concert with this, many operators are enlisting large fans, as this helps with airflow and movement to drive the offensive air through your air handlers or through open roofs/windows.
Supplemental systems like ozone, UV, water clarifiers and electronic controllers can be valuable tools to improve system performance, added Bokowy. "They are not, however, an answer for everything. These systems can offer specific performance benefits to address specific problems in your aquatic facility. It is important to research all of these options and understand what value they might provide to your specific environment."
Technology is indeed helping with all these issues, explained Steve White, a Certified Pool and Spa Operator, Instructor and Inspector, and the owner of Underwater Pool Masters, West Boylston, Mass. "Instead of just using the oxidizer and the sanitizer," White said, "we have UV lights, which can be used to kill elements in the pool that we are trying to remove, which the chlorine and bromine can do, but it's supplemental. In the process, the UV gives us less reaction because most of the things are eliminated earlier in the system, as the water goes through the plumbing. Most modern pools will use UV. Ozone is an excellent oxidizer, and also can contribute to the elimination of some of those reaction gases that occur."
Cloudy water is often the first visual clue of a problem, Bokowy said. "It may be a chemical problem, or it may be related to a physical component like circulation or filtration. Do not make immediate assumptions that it is one or the other. Investigate all possibilities until you can identify a root cause and take action."
Other problems may be indicated when you or users notice an offensive smell, or even burning eyes and respiratory issues. The offensive smell is caused from a reaction between the chlorine used to sanitize and oxidize to keep a pool clean and with nitrogen-containing contaminants, such as ammonia. This reaction creates chloramine, Beireis said. "The chloramine is what is creating the problem and the offensive smell we associate with indoor pool facilities. We realize we have chloramines by doing our simple chlorine test and determining our combined chlorine. Combined chlorine is the level of chloramines we have in our water."
Ammonia in the water is a definite problem. Where does the ammonia come from? "Well," Beireis said, "typically from those entering our pools. Those sweaty people. Our pools would be pristine if it wasn't for them, right? All the sweat, urine, body products they bring into the pool create part of the chloramine, but not all of the problem. We are fighting the chloramine issue with the water we use. Water treatment uses chloramines for our drinking water so it is coming into our facility every time we add water. There is nothing we can do with this inorganic chloramine that is coming in from the water source, and so we focus on the organic."
Why don't you seem to notice chloramines at outdoor pools? Do they not have them? "Yes," Beireis noted. Outdoor pools can still have chloramines but air movement and UV from the sun help reduce or prevent organic chloramines. Indoor pools can have issues with airflow and moving the chloramines and so you have a buildup effect in the atmosphere.
"We indoor operators are constantly battling the chloramine issue due to our closed atmospheric systems," Beireis said. "In order to combat this dreaded chloramine issue we replace water, super-chlorinate to reach break point chlorination to release the chemical bond, and release the ammonia compound, use ultraviolet system and or ozone, introduce potassium monopersulfate and look at improved air handling."
Additionally, he said, it seems indoor facilities continue to play with design components from high ceilings to low ceilings, open roofing and windows, and ducting high or low or in between to draw and push air. "Now we are seeing introduction of fans to move more air," he said.
Other problem areas are corrosion on lead, copper and metal, caused by ammonia. "Go to an indoor complex and start looking carefully at all the metal," Beireis said. "You undoubtedly will start seeing rusting or corrosion. It is a constant maintenance issue to stay ahead of the corrosion. Keep the chloramines as low as possible. Realize you will never completely eliminate them, or at least for not long."
Diligence is the key. You have to constantly deal with potential problems and look for ongoing solutions. "You may install a UV system or work on better airflow when you reach breakpoint chlorination so the off-gassing can go somewhere and not right back to where it originated. It is a constant cycle," Beireis said, "but you can win the battle as long as you are committed to being diligent with your combined chlorine testing and then reacting to correct things when the numbers start creeping up."
The bottom line in dealing with water and air quality is neatly summed up by Lachocki: "In our industry's case," he said, "what's good for the patron is good for the pool industry. No one goes to the pool because they want red eyes. They go to have fun. And, if they come to the pool often enough, there is a side effect. They get fit and are happier."