Safer Swimming, Safer Breathing
Managing Water & Air Quality
Craig Markey can attest to the effectiveness of new technology and its impact on the air and water quality of an indoor aquatic facility.
Markey, the associate director of recreation and aquatics at Penn State Harrisburg, oversees the operations of a six-lane, 25-yard pool that hosts students, faculty, staff and the community for lap swim and open rec swim. The school offers kinesiology classes as well as learn-to-swim, and lifeguard and water safety instructor classes.
Like every indoor pool environment, PSH's facility needs to manage water and air quality for the safety of swimmers, staff and spectators. The daily project cannot be seen as two tasks, as water quality affects air quality. The chemical reaction that occurs when free chlorine meets byproducts from bathers—sweat, urine, feces, lotion—produces chloramines that can cause harm to lungs and skin.
The toxic output is inevitable, so even the finest management of water chemistry will result in chloramines rising into the air. Circulation of that air—replacing the old with the fresh—is crucial to ensuring safe breathing. Markey said the recent installation of a new system for water quality has improved both water and air at his facility.
"Since the installation, the air quality has been much better than with the previous unit," said Markey. "The water is balanced and chlorine maintained at a level high enough to oxidize, while minimizing the chloramines in the facility. The balancing and ensuring a negative pressure is important as it relates to the other connected parts of the facility.
"Adding a UV light, while not critical when everything is balanced, definitely has helped and provides a secondary disinfection system as the water circulates."
Markey's story illustrates the interconnected nature of pool facility management by hardware, software, operator education, swimmer policy and regulations. Coronavirus has introduced an obstacle; the virus itself can be degraded by regular pool and pool area disinfection, but the public health safeguards limiting gathering gut fitness facilities the same as the travel and hospitality industries. The very nature of the facility is to gather people for activities.
That said, everything pools did pre-pandemic—water chemistry management, air turnover, deck disinfecting—is effective at degrading the virus.
Steve Pearce, co-founder and executive vice president of an Atlanta-based provider of water treatment solutions for pools, said COVID puts increased importance on a facility's air quality. But in a twist, air quality should be better with fewer bathers, because there is less contaminant to turn chlorine into chloramines.
"Being in the water is no problem because there's constant chlorine—the CDC reviewed it and said chlorine kills the virus—but you have parents and bathers that are afraid to be in indoor facilities because there's recirculated air and they're breathing what everybody else is breathing," Pearce said.
Outdoor pools aren't as dangerous, said Pearce, but in most of the country outdoor pool weather is over for 2020.
"It's a big worry for the aquatics industry, what's going to happen this fall and this winter because if you can't get bathers to come inside, whether you're a swim school or a competition facility or a resort with an indoor pool, you can't survive," he said. "The focus for the past few years in the pool industry has been water and air quality, and now it's how to keep the doors open."
Juliene Hefter is executive director and CEO of the Association of Aquatic Professionals. She also teaches classes in water and air quality management. Hefter believes pools are more than revenue generators and should be maintained as true assets to communities.
"It's a lifesaving facility," she said. "You can be in the pool from cradle to grave. Babies to 100 years old. Those pools are teaching people lifesaving skills and swim lessons. The cost of saving lives is a lot less than not saving lives."
Hefter's point is that any amount of money and time spent to ensure the best water and air quality is worthwhile. But all the best technology is blunted by the lack of one thing, she said.
"You can purchase equipment that can help ensure (air and water quality), but it still comes down to operators knowing what they're doing," she said.
"People get thrown into running and operating an aquatic facility, the technical side of it, without much training. We see that a lot. It's getting better. People are starting to understand the importance of training and educational opportunities. Our facilities aren't cheap, and we want to protect the investment. I still get people coming into our classes who have never done anything with a pool and they're in charge of one and it's scary for them."
"Education is 99% of this business," he said. "There's a lot they don't know, opportunities for something better they aren't aware of. If there's a guy running a facility for 30 years and he's been doing it one way, it's very difficult to change that. He knows it may not be the best way, but he's used to doing it that way and that's the way he likes it."
Hefter said keeping water safe historically has been better known and practiced than maintaining good air quality. Originally facilities were built air-tight because the goal was to keep the heat in for energy saving.
"This caused a lot of problems because when you have people enter your pool they bring a lot of different things, and we get a buildup of combined chlorines which comes from nitrogen in the water and what happens if we don't have good air quality, that buildup in the water will get high," Hefter said.
"We super-chlorinate to get rid of them, and we put in a whole bunch of chlorine and it burns off those chloramines and it starts kind of like a fire in the water and it's like a pile of leaves. If it doesn't have a lot of circulation and oxygen it'll just smolder, but if you have a lot of air and air circulation it'll burn really hot and just dissipate."
She said in an indoor pool without good air circulation, chloramines dissipate and go into the air but if they have nowhere to go, they'll go to the area of least resistance, which is back in the water.
"The only way to get good air circulation was to open up the front doors, open up the back doors and turn on big huge fans to blow the chloramines outside. You see that with a lot of these facilities because they're so air-tight, and they don't have good air circulation. Newer facilities are taking into consideration those types of things."
Building specifications are bolstered by air circulation technology. Markey said his newest air quality hardware and software is a huge improvement from his former unit.
"The ability to evacuate all the air with spectator mode is great to quickly change the air based on current need," he said. "This was a great feature the other unit didn't have. While not used often, it is nice to be able to quickly 'clean up' the air, and would be excellent when having a larger event."
Pearce said chemistry works against the quest for air quality; the chemistry of the water is what creates the air quality issues. Unfortunately, what's used in a pool to make water safe also creates byproducts that create air quality issues.
He said it's impossible to get rid of the byproducts completely, and it's impossible to keep the air completely free of any of these compounds, but there are ways to reduce them. The biggest problem is that the chlorine that is essential to destroy bacteria reacts badly with the ammonia that is introduced with sweat or urine. When that ammonia mixes with chlorine, it creates a chloramine that rises off the surface of the water and creates the smell most people associate with pools.
"Therein lies the problem," Pearce said. "You have people releasing ammonia and you have chlorine, and the only way to successfully reduce those chloramines in the air is by adding additional technology. UV or ozone are typically the most prevalent additions that will reduce the amount of chloramines, but you're never going to completely get rid of them because you're always adding chlorine and you're always adding ammonia."
UV and ozone systems are pass-through systems so pools only get the benefit of those two additional bacteria killers when the water passes through the chamber, Pearce said, but bathers are adding ammonia to the water all the time.
"So the trick for a commercial pool is, how do you keep the air as chloramine-free as possible when the two ingredients to make chloramines are present all the time?" said Pearce. "That really is the trick for all manufacturers, and anyone involved in technology is trying to come up with the magic bullet."
Pearce said that until that magic bullet is invented or discovered, the only answer to improving water quality is to throw UV and ozone technology at it. Attacking air quality is the same, and the process simple.
"Air changeover is a big deal," said Pearce. "The more fresh air you bring in and the more chloramine-infested air you move out, the better the air quality."
The flip side is, because when facilities exchange the air in the winter—cold air brought in and warm air sucked out—the heating bill spikes. The opposite is true in the warmer months. That's the fine line operators must toe—how much fresh air to bring in, how to control the chloramine, with UV or ozone, and finding the break point in wanting to pay for additional heat or air conditioning versus keeping the air as clean as possible.
"Chlorine has got to be in the water, there's just no option," he said. "You have to have bathers, because otherwise what's the purpose of the pool? It's just because of the nature of the way a pool circulation system works, there's turnover times and it takes a certain amount of time for all of that water to get through whatever that technology is to help reduce the chloramine. Until there is something to put into the pool to stop that reaction from happening, it's going to happen.
"Unfortunately you add stuff to the pool to stop that reaction, you stop the chlorine from being effective and then what's the use of having the chlorine because now people get sick because there's not enough chlorine."
Pearce said management encompasses a combination of things. The most successful pools with the best air quality have a plan laid out for how to manage their pool properly—keeping free chlorine controlled so there aren't huge spikes of free chlorine that cause additional chloramines, adding a secondary disinfectant like UV or ozone, and a successful turnover or dilution protocol in place that turns over water and turns over air to allow that chemical makeup to continue to happen.
"It's very difficult to get rid of something without getting rid of what you need," said Pearce. "You want to get rid of the chloramine, but you don't want to get rid of the chlorine and it's difficult to do successfully."
Pearce said budgets for hardware and software are obviously a limiting factor for facilities, but were they not, he recommends:
>> On-site chlorine generation. "It is the best by far because you're not introducing any byproducts into the water, you're just making simple elemental chlorine and there's nothing else for the reaction to occur," Pearce said.
>> Adding ultraviolet light. "It is the most efficient way of reducing chloramines," Pearce said. "Add an ORP/PPM /pH control system to marry all those technologies together to control the free chlorine in the water at the optimum level as consistent as possible all the time."
>> Air handling unit with ability to adjust based on number of bathers—more bathers, more turnover and vice versa.
>> Controllers that can handle all of it. "They can control the chlorine, the pH to make sure the chlorine is as active as possible, and the air handling units to make sure the air switchover is optimal for when there's the most bathers," said Pearce. "If you marry all those together you have by far the best system possible. Unfortunately it doesn't come cheap."
The most common issues facilities are trying to fix include upgrading systems, said Pearce. The majority are looking to be more efficient, getting into the 21st century in how to control water while saving energy.
"It's difficult to control (water) when you have chemicals on site and you have a 16-year-old lifeguard taking care of things," said Pearce. "The chances of issues are high, and a lot of (facilities) look at changing (systems) just for that reason."
Pearce said the expense can be handled with lease plans; water and air safety should not suffer because of funding.
"Water and air quality are very important," said Pearce. "It's really important especially in places like swim schools, which are very much affected by air quality because you have all those instructors in the water eight to 10 hours a day breathing that air in all the time, and you have the kiddos with young lungs breathing it in. It's essential they have their air quality controlled properly.
"A big Great Wolf type waterpark is important but not as important as a swim school where you've got 1-year-olds learning to swim. Our equipment is in a lot of swim schools across the country—adding the UV in order to control the chloramines is a big deal, and they all do it because they're very concerned about the air quality."
Carl Nylander, a principal at Counsilman-Hunsaker, said when the Model Aquatic Health Code (MAHC) was initially developed, the ventilation and indoor air quality technical committee recognized that current ASHRAE baseline recommendations were insufficient for many aquatic facility types.
He said ASHRAE calls for a minimum amount of air (0.48 CFM/SF) based on the overall pool size. However, the standard doesn't address the volume of the natatorium space, which can vary tremendously depending on the facility type and function. Additionally, ASHRAE acknowledges the additional moisture load from other pool types beyond traditional lap pools. But these "activity factors" can be generic and don't address all situations for designers.
Nylander said the air quality recommendation portion of the MAHC is a current focus.
"It was acknowledged that additional research and data was needed before bringing these recommendations into the body of the code," said Nylander. "An ad hoc committee of industry experts has been convened during the current Council for the MAHC cycle to further analyze the data, with the goal of reaching a consensus to propose air system design requirements that are not just based on the air delivery rate but also the bather load, amount of fresh air, types of aquatic amenities, and distribution of air within the natatorium." RM