Feature Article - November 2019
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The Air in There

Managing Air Quality in Aquatic Facilities

By Joe Bush

State-of-the-art chemistry control systems are wireless, programmable in many ways and can also handle alkalinity levels and the addition of ultraviolet germicidal irradiation disinfection.

"Some UV systems are installed and run full blast," Steinbrueck said. "We have systems that can monitor the combined chlorine and ramp up the UV system when there is higher combined chlorine and down when there isn't so much."

Steinbrueck said operators have to be cautious when considering controller systems; know the expected bather load on the body of water before shopping. Ask suppliers to audit the facility and program's needs and make recommendations, Steinbrueck said. How many swimmers there are and what type of swimmers is crucial.

"It's about load and how it's used," he said. "Generally speaking, you're looking at the surface area that's exposed and the bather load and type of bather load. The heavier the bather load, the more organics, the more chlorination, the more chloramines. The controllers are responsive enough to demand. It's more a matter of understanding the load you expect to see and having feeders that can deliver the load of chemicals fast enough."

The next step is to marry the water controllers with the air-handling systems, said Steinbrueck, and that is happening. That process begins with the installations of each system, or both, depending on whether the situation is new construction or a renovation.

"Generally speaking, the air-handling people don't know that much about pools, so they really do need some support to make this work," Steinbrueck said. "When you look at it as a whole system instead of as a pool or as air, you end up with a really nice opportunity for improvement."

Potential issues with air quality begin with water quality. When chlorine is turned to chloramines—combined chlorines—there's volatility that leads to escape from the water surface. The gas sits just above the water and is inhaled by the pool users, then rises to be inhaled by people on the deck—lifeguards, parents, coaches and spectators.

When people who are not in the water begin complaining about irritated eyes and difficulty breathing, something needs to happen to the air. The answer is circulation and exchange, the job of the HVAC system. Fresh air is brought in from outside, replacing the old air.

How much outside air is brought in and how fast are the calculations needed to maximize air quality. Also at issue for facilities in winter climates is the heating of the air brought in.

Tom Carrico was a swimming coach at the youth, high school and college levels before starting Carrico Aquatics, a company that helps facilities with water quality, operations and maintenance activities, equipment status, operation cost, preventive maintenance and budgetary considerations.

He's seen lifeguards with lifeguard lung from breathing chloramine-filled air, and coached kids who developed asthma from hours at and in pools. Carrico said his company attacks unsafe water and air comprehensively.

"We'll put in a chlorination system, we'll put in UV, and then we use a controller with a variable frequency drive," said Carrico. "The system tests combined chlorine, and if the combined chlorine starts to increase, it will send a signal to the air handler that tells the air handler to start exchanging the air.

"If we speed the exhaust fan up, it'll cause the supply fan to bring more air into the room. As our water starts to get dirty, we start exchanging the air in the room. As the air gets cleaned, we can slow that down and use the same air over again so what we're doing is maximizing the oxidation rate in the pool water, killing off everything we can, and what we can't kill we measure and tell the air handler it needs to exhaust the air in the room.

"What has happened is, we've eliminated chloramines in indoor pools, but the second thing that happened that we were not expecting to happen is we have reduced energy costs by up to 40 percent."

The energy savings happens when less is spent moving air when the pool is in less frequent use and less heat is used to warm cold air brought inside in the cooler months, Carrico said. This system can be enhanced with air exchange that sucks the old air from the room at the pool level rather than higher up, said Carrico.

Don Baker is CEO at a South Carolina-based company that manufactures a system specifically designed to pull air from the pool surface and send it out of the building. After a Greenville, S.C., pool was condemned for the corrosive structural damage caused by chloramine-filled air, one of the pool's volunteer coaches, himself an engineer, decided to approach the problem differently. Instead of protecting structures from the air, he sought to remove the air.

The resulting product can be placed on the deck or in poolside gutters or in walls and works with a facility's dehumidification system.

"If chloramines can destroy metals, what are they doing to our kids?" asked Baker, who is on the same MAHC indoor air committee as Schallock. "Poor indoor air quality for pools is as significant as concussions are for football. I will not let my grandkid swim indoors unless the pool is operated properly and they have a well-designed and operated air handling system." RM