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2014SumShotcreteEMag

Pool & Recreational Shotcrete Corner the equipment room containing a high concentrate in the water and respiratory issues for exposures of salt water that is mixed to create a low-concen- just above the water. Each of these devices greatly tration salt/chlorine-water solution. This chlori- reduces the demand for chlorine and, when com- nated water solution is then injected into the pool, bined, can significantly reduce chlorine consump- which is similar to the way liquid chlorine would tion, making it easier to safely maintain a very be injected into the pool. This type of system for low level of chlorine in the pool. a large pool is quite large and takes up a lot of A lot of these items are specific to all types of space in the equipment room. During the pool swimming pools, whether they are shotcrete, liner, design process, the salt chlorination system is not cast-in-place, or any other method. However, prop- always taken into account and the area for the erly placed shotcrete is the best product to withstand chlorine salt-generation tank ends up under-sized any of the negative effects that salt can have on the and uses a smaller tank that cannot keep up with structure. Liner pools typically have more exposed the demand of a large commercial pool. metal pieces and cast-in-place pools have planned The other commercial-style saltwater system construction joints. Shotcrete pools are monolithic is similar to the residential version with a gen- and the only metal portion is the embedded rein- erator that ionizes the molecules. This requires a forcing bars. With a suitable concrete mixture very large unit. The unit is so large that it can send design and proper nozzling technique, the oppor- an ionizing electrical current throughout the entire tunity for the chlorides in the salt water to penetrate pool and as a result, attacks anything metal, to the reinforcement is substantially reduced. Cast- including the heaters, pump components, railings, in-place pools have construction joints that have a lane line components, and lights. Thus, pools higher chance of allowing the salt water to penetrate using this type of system need to be built with to the reinforcement and cause corrosion problems, all-plastic components that can resist the ionizing especially if the waterstop is improperly placed or currents. The items that cannot be plastic, such as poorly encased. Epoxy-coated reinforcing bars can heaters, flow meters, and other sensors, must be be used if there is concern regarding the salt water specifically designed for service in saltwater reaching the bars, but if not properly handled, pools. Additionally, sacrificial anodes need to be breeches in the coated reinforcing bars in the field installed to try to compensate for the ionizing can actually cause more corrosion problems than current. On top of all the saltwater requirements uncoated reinforcing bars. Epoxy-coated reinforce- for a commercial pool, some states and munici- ment is not necessary when proper construction palities still require a backup chlorine system methods are used. which is powerful enough to keep the pool online In summary, saltwater pools certainly have should the salt system fail. As a result, salt systems some comfort benefits for the user. However, the for commercial pools can be costly to install. challenges in designing, building, and maintaining The alternative to a saltwater pool is the more these systems need to be considered in the overall common liquid or pelletized chlorine. However, cost-effectiveness of the pools. Though saltwater there are also other technologies used in municipal pools do reduce the amount of chlorine needed water treatment facilities being brought to swim- for disinfection, alternative systems like UV and ming pool disinfection systems. Ultraviolet (UV) ozone can be just as (or even more) effective. and ozone disinfection are two systems that, in combination with conventionally chlorinated pools, actually maintain a lower chlorine level than with salt systems. In turn, a pool ends up with Mason Guarino started in the as little chlorine as legally possible. The UV pool industry when he was 14, system is simple. The water passes through a learning how to install rein- chamber exposed to correctly powered UV light forcing bar. Since then, he has that kills the bacteria and germs in the water worked on all phases of swim- system. It can even destroy the chlorine if it is ming pool construction. Gua- turned up too high. The ozone disinfection system rino has been with South Shore creates ozone and injects it into the pool water Gunite Pools & Spas, Inc., system at the pump. The ozone also kills the full-time since graduating from the Wentworth bacteria and germs, as well as actively breaks Institute of Technology with his BS in construc- down non-living waste products in the pool water tion management in 2009. Guarino currently that can combine with chlorine, causing unhealthy serves on ASA’s Board of Direction and is an by-products that can irritate the skin submerged ACI Certified Nozzleman. 30 Shotcrete • Summer 2014


2014SumShotcreteEMag
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