Make sure water and air quality are in sync
First and foremost, water and air quality are dependent on each other. The latter, however, is affected by:
- The amount of fresh air that is introduced into the building every hour. This is dependent, of course, on outdoor climate and building type. A 90 per cent change of air every 20 to 25 minutes works well in warm areas.
- The condition of the air handling equipment. Filters should be cleaned or changed every three months. Micro-filters are also available, which help to remove more airborne contaminates than standard fibreglass or paper filters.
- The type of air handling system installed in the building.
- The lack of routine maintenance. Maintenance must be performed and tracked on all air-handling equipment. Vents and louvers must be checked and lubed at least four times a year to make sure they are working properly. Dust must be removed from the surface of vents, while motors, belts, and fuses also need to be checked.
Chloramine formation can be caused or accelerated by:
- Bathers not showering properly before entering the pool.
- Bodily wastes in the pool such as urine, which prompted the 2015 campaign by the U.S. Centers for Disease Control (CDC), Water Quality and Health Council, and National Swimming Pool Foundation (NSPF) to educate the public on the myths associated with urinating in the pool.
- Bathers performing a high level of aerobic activity and sweating in the water.
- Residues from ammonia-based cleaning products used on pool decks or in shower rooms/lavatories.
- Residue from fertilizers used on landscaping (nitrogen-based) that get tracked into the natatorium.
- Poor air circulation and a lack of fresh air being introduced into the aquatic facility.
- Over ‘shocking’ the pool. This is not a routine maintenance procedure. It should only be performed to kill bacteria, which has been found via lab tests.
- Improper use of certain brands of chemicals not suitable for conditions specific to a geographic area.
- Municipality adding chloramines to tap water. This treatment is called chloramination and involves adding chlorine and small amounts of ammonia, one at a time, to the water which react together to form a chloramine disinfectant.
In short, it is common for indoor pools to notice the absence of the chlorine smell within days after the installation of a UV sanitizer. These systems are plumbed in after the pump and filter, before the heater or chemical injection points. UV is non-corrosive; therefore, using it to remove chloramines also makes the pool environment less corrosive. Further, other pool equipment installed after the UV system will also benefit from less corrosive conditions.
When considering the installation of a UV sanitizer, it is important not to oversize the unit, as an increased dose (the product of UV light intensity and time, which is sometimes referred to as millijoules/cm2), can strip halogens out of the water. Should this happen on a pool using automatic injectors, there can be an increase in chemical consumption, which will lead to more byproducts. By properly sizing the UV system, chemicals can be more effective in smaller doses.
In conclusion
Unfortunately, RWIs are dramatically increasing. It has also been established that certain pathogens are resistant to chemicals, thus leading to various diseases, including respiratory, skin, and gastrointestinal problems. Awareness and concern about exposure to disinfection byproducts (DBPs) in pools and spas/hot tubs has further increased the notion of air quality. Therefore, a paradigm shift is needed on how pool and spa/hot tub water is treated.
UV disinfection is recognized as an effective and reliable method for deactivating pathogens in the water and reducing bather exposure to DBPs. And, the fact air quality can also be improved helps aquatic facilities increase overall bather comfort.
Jeff Boynton is the general manager of Delta Ultraviolet Solutions, a manufacturer of UV-C technology in Gardena, Calif. He is responsible for managing the company’s existing customers as well as growing sales in North America. Boynton has worked in the swimming pool and hot tub industry, primarily in Europe, for more than 25 years. He can be reached via e-mail at jeffb@deltauv.com. For more information, visit www.deltauv.com.
There is actually a sixth option to reduce chloramine development in the pool environment that was not mentioned. It is not remedial or secondary in nature as are the others, but rather simply the most efficient primary chlorination method being applied within the commercial pool industry. This option is known as High Capacity Venturi Injection. It enables a pool system to stay ahead of the chlorine demand effectively completing the process of oxidation while reducing chlorine use by as much as 40%. UV is a secondary sanitation system effective in reducing existing chloramines which should be considered after the application of a properly sized venturi feed system capable of high capacity feed (#HCF). RB
Actually there is a far superior system available for the prevention and removal of the problematic nitrogen trichloride which causes the corrosion and trihalomethanes which bothers the swimmers. Over one million people swim in pools treated with Hydroxan everyday. Recreational water Treatment must take place in the pool or spa where the bathers are to prevent cross infection and be testable acording to microbiologist Dr Robert Stern. Hydroxan is the low cost answer with 30 years of success.