Should there be air movement at the water’s surface?
At Dectron, we are often asked about the importance of air movement at the water’s surface and whether this contributes to good IAQ in an indoor pool facility. And it does!
The U.S. Olympic Committee (USOC) recommends there be some air movement at the water’s surface to dilute a higher concentration of chemicals where swimmers breathe.
While it’s important to have some air movement, significant air movement at the water’s surface (above 30 fpm per ASHRAE) is not recommended and will not improve IAQ. In fact, significant air movement will increase the evaporation rate (increasing the dehumidification load and pool water heating requirement) and affect the comfort of swimmers.
For the complete answer, including how to both ensure there is adequate air movement and control and reduce airborne chloramines at the water’s surface, please visit Dectron.com/Paddock.
Better Together
In case you missed it: Paddock Pool Equipment Co is helping us provide two children with swim lessons through Step Into Swim for every Dectron unit sold with a Paddock Evacuator®.
We’re better together. With Paddock’s support, we are not only helping ensure more children learn how to swim, but we are also significantly improving IAQ for swimmers and the Team Behind the Swim Team. Learn more: Dectron.com/Paddock.
Step Into Swim, in partnership with Every Child A Swimmer, is a Pool & Hot Tub Alliance initiative committed to safe swim education and drowning prevention and is run by Rowdy Gaines, 3x Olympic gold medalist and Dectron’s 2022 IAQ spokesperson.
How is the Paddock Evacuator set up with HVAC?
Ensuring Paddock Evacuator Technology is included (if it makes sense given the operating conditions and expectations of the facility) when selecting HVAC equipment designed for the facility is a great way to ensure good IAQ from the get-go. In fact, exhaust air is one of four key factors that have the most direct effect on IAQ and are under the design engineer’s control.
Below are a couple ways the Evacuator can be integrated with HVAC:
Provide a dedicated air path, the EF1, and use the dehumidifier’s exhaust fan.
Provide the dedicated air path, the EF1, and a heat recovery coil.
For the complete answer, please visit Dectron.com/Paddock.
What can facility owners, engineers and contractors do to create the optimal indoor pool environment?
Creating the optimal indoor pool environment is no easy feat. There are so many critical considerations that can affect the health and comfort of swimmers and their supporters as well as the structural integrity of the building. Below are three key considerations for facility owners, engineers and contractors striving to create the optimal indoor pool environment. (For a more comprehensive resource, please check out our Natatorium Design Guide.)
- Ensure supply air gets down to the breathing zone (at the deck level and water surface). The most important focus of the HVAC design is to provide adequate supply air down into the breathing zone. It’s critical for both comfort and good IAQ. The supply air from the HVAC system has been conditioned and filtered with outdoor air blended in. When supply air is delivered down into the breathing zone, swimmers, coaches and volunteers enjoy the best possible air quality.
- Control temperature and humidity. There are special temperature levels in an indoor pool environment that swimmers and their supporters in the facility expect, and space temperatures in an indoor pool facility are unique to each project (i.e., the ideal temperature range for a competition pool is different than that for a swimming school pool for children). As for humidity, relative humidity levels outside the optimum zone 40-60% range can lead to poor IAQ and put the health of occupants at risk.
- Address airborne chloramines early on. Chloramines off-gas from the pool water and build up over time, threatening the health of swimmers and the integrity of indoor pool facilities. Facility owners, engineers and contractors can address the issue of airborne chloramines when choosing HVAC equipment designed for the facility.
Our equipment can be built to accommodate Paddock Evacuator Technology, a source-capture system designed to minimize levels of airborne chloramines and disinfectant by-products (DBPs). When designing a natatorium, engineers first need to meet with the facility owners to discuss operating conditions and expectations then ensure Paddock Evacuator Technology is included when selecting their HVAC equipment. Learn more on our website.
What does it mean when there is such a strong “chlorine” smell?
When you walk into an aquatic facility—or any other building with an indoor pool—you might notice an odor you think is chlorine and you might even associate it with cleanliness. What you smell though is not chlorine at all, but harmful chloramines.
Chlorine is added to indoor pool water to address the nitrogen-containing compounds brought in by swimmers (think sweat, saliva, hair, skin and urine) and keep the water clean. If the introduction of these nitrogen compounds outpaces the introduction of free chlorine, the chlorine combines with the nitrogen compounds (rather than fully oxidizing them) to produce chloramines (combined chlorines). What results? Higher chloramine levels in the pool water and an increase in chloramine off-gassing, causing the odor many people mistaken for chlorine. Monochloramine, dichloramine and trichloramine are the three different types of chloramines that can form.
Far from an indication of cleanliness, this odor tells you that there is not enough free chlorine to address the nitrogen compounds in the water and that airborne chloramines may be putting the health of swimmers and the integrity of the facility and its equipment at risk.
Dectron equipment can be built to accommodate Paddock Evacuator® Technology, a source-capture system that pulls trichloramines from the water’s surface and, with the help of HVAC equipment, exhausts them outside the facility to significantly improve IAQ. Learn more about Paddock Pool Equipment and Dectron on our website.
How do indoor pool owners ensure that good IAQ is maintained?
Indoor pool owners play an important role in maintaining good IAQ for swimmers and others who use or work in their facility. Here are a couple of ways owners can ensure good IAQ:
- Have an air distribution system that supplies sufficient air to the breathing zone, including across the water surface, and addresses areas prone to condensation (e.g., exterior windows). It also important that the HVAC system blends in the correct amount of outdoor air according to codes and that the grilles/diffusers have adequate throw distance to direct air where it needs to go.
- Control, reduce and eliminate chemicals off-gassing. It is possible for an indoor pool owner to address poor IAQ caused by chloramines (the chemical byproducts of chlorine doing its job) while choosing HVAC equipment. Dectron equipment can be built to accommodate Paddock Evacuator® Technology, a source-capture system that pulls trichloramines from the water’s surface and, with the help of HVAC equipment, exhausts them outside the facility to significantly improve IAQ.
Indoor pool owners can also reduce contaminants entering the water and ultimately trichloramines by establishing an effective patron hygiene program. Ensuring a successful program may mean encouraging swimmers to shower prior to entering the pool, educating facility staff on the importance of it, posting signage about it inside the facility, frequent scheduled bathroom breaks during swim lessons and practices and not allowing street shoes, food, etc. on deck.
Technologies such as UV water treatment are available as well.
Learn more about Paddock Pool Equipment and Dectron on our website.
What are trichloramines and how do they affect the health of swimmers?
Chlorine is an oxidizing sanitizer added to indoor pool water to keep it clean; it attacks organics in the water, such as hair, skin, urine and saliva. Chloramines, the chemical byproducts of chlorine doing its job, off-gas from the pool water and build up over time. This is a result of the oxidizing process, and all indoor pools generate off-gassing Disinfectant By-Products (DBPs). If not addressed though, trichloramines, the most volatile of chloramines, can put the health of swimmers and the integrity of the facility and its equipment at risk.
Trichloramines are heavier than air and hover at the pool surface, where exposure to irritants is greatest.1 Trichloramines are a health hazard known to irritate swimmers’ eyes, skin and respiratory tract.2
It is important for facility owners to address trichloramines to protect the health of not only swimmers but also their parents and other supporters in the stands, coaches, volunteers and facility managers. Dectron equipment can be built to accommodate Paddock Evacuator® Technology, a source-capture system that pulls trichloramines from the water’s surface and, with the help of HVAC equipment, exhausts them outside the facility to significantly improve IAQ. Learn more about Paddock Pool Equipment and Dectron on our website.
Sources:
- Study of Source/Capture of Airborne Chloramines, Paddock Pool Equipment Company
- Chloramines & Pool Operation, Centers for Disease Control and Prevention