Problem Solver - August 2011
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Prevent RWIs at Your Pool

Aquatic facilities today are dealing with trends that make them more likely to face the consequences of recreational water illness. Aquatics continue to grow in popularity, and with more users in the pool, there are more chances of someone spreading an illness. What's more, experts are finding higher concentrations of contaminants. Other trends, such as warmer water and spray features, also present challenges.

On top of this, many facilities have had to deal with issues that arise when chlorine combines with various outside factors, such as skin, urine, sweat and more, to create chloramines. Chloramines have been connected with asthma among competitive swimmers. In addition, the use of dangerous chemicals and constant inhalation of air tainted with chloramines is a health risk for employees.

All of these trends combine to create a new environment in which recreational aquatic venues are becoming more like the communal bath tubs of old.

Because of all of these challenges, we are seeing an increase in regulation at both the national and state levels, and the Model Aquatic Health Code aims to offer states and localities a means to create their own requirements that adhere to scientifically proven and peer reviewed industry wide standards.

Q: What kind of solution should I look for to help address the rising incidence of RWIs?

A: UV disinfection is an ideal solution. UV light has the ability to destroy the cross bonds in the DNA contained in the nucleus of an organism, or RNA in the case of a virus. The damage denies basic cell functions of replication, respiration and assimilation of food. Without these functions, the organism quickly dies. In addition, UV systems are able to effectively remove chloramines. All of this means that UV can provide safer water and air for your aquatic facility.

Q: What should I know when selecting a UV system?

A: When selecting a system, you should be aware that system sizing is critical. Three variables should influence your decision: the turnover rate of your venue's water; the use of the water (bather load, age, competitive vs. leisure use); and the transmittance of the water. This is not necessarily the clarity of the water. Clear water still has the potential to have all kinds of suspended solids in it that affect performance. This refers to the fraction of light transmitted through water.

If not sized properly, the UV system will function but it will not perform effectively. Many systems are available that have been designed for drinking water applications and are sized for water with 98 percent transmittance. But recreational water has a transmittance range from 90 percent to 95 percent. A UV system sized for a facility based on the wrong transmittance will not function properly. To protect against this, you need validation.

Q: What is validation, and how can it help?

A: Validation of your UV system provides a recognized third-party verification of performance. It can reduce risk because performance statements can be related to validation. The owner/operator and the local health inspector will be able to tell if the disinfection system is performing properly.

There is no additional cost involved.

While no silver bullet can take care of all the issues faced by operators and owners of aquatic facilities, a combination of best practices and the use of validated UV systems can dramatically reduce the risk.


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