What is Ultraviolet (UV) & How it is Applied to Swimming Pools?
Wednesday, November 21, 2018
The strong smell of chlorine within an aquatic facility is not a sign that the pool or spa is clean. It's actually a signal that there is something wrong. Luckily, there is an application that can be added to your swimming pool recirculation system to help correct this issue, and create a safer and more enjoyable swimming experience - An Ultraviolet (UV) system.
From a hydrotherapy spa to the largest Olympic-sized competition pool, UV sanitation systems are quickly becoming (or have already become, in some municipalities) the most popular method of additional water treatment in the aquatic industry. UV not only destroys chloramines, the unpleasant by-products of chlorination, but it is also a highly effective disinfectant (although the need for chlorine is reduced with the use of a UV system, it is still needed to ensure proper disinfection).
Chloramines are formed when free chlorine reacts with sweat, urine, and other contaminants in pool water. Trichloramines, in particular, are powerful irritants which are responsible for eye and respiratory complaints and the unpleasant ‘chlorine smell’ commonly associated with indoor pools. Chloramines are also corrosive to the surrounding area, and in time can lead to damage to pool accessories, buildings and structures, such as railings, ladders, and ventilation ducts. Any water treatment system that reduces these unwanted conditions is therefore welcome.
UV harnesses the power of ultraviolet light to eliminate microorganisms, lower chemical usage, and eliminate toxic by-products.
WHAT IS UV?
UV is a highly efficient, natural disinfectant that nutralizes virtually all known microorganisms, including bacteria, viruses, and molds and their spores, by permanently destroying their DNA.
Ultraviolet light is a naturally occurring component of sunlight. It falls in the region between visible light and X-ray in the electromagnetic spectrum. The mechanism of UV disinfection is strong sunlight that disinfects water by permanently de-activating bacteria, spores, moulds and viruses.
These systems reproduce UV radiation inside light chambers via powerful lamps, which emit germicidal UV-C light that is used to disinfect pool and spa water.
UV-C causes permanent damage to a number of microorganisms almost instantly as the water circulates through the light chamber. By disrupting the microorganism’s DNA, protozoans, viruses and bacteria are unable to replicate and remain inert. This light, however, works only on water that flows through the chamber.
HOW IS UV APPLIED TO SWIMMING POOLS?
Ultraviolet is a recommended application that can be added to any swimming pool. However, it should only be used as a secondary pool water disinfectant. A primary disinfectant, such as chlorine or bromine, still needs to be used at all times. Chlorine/bromine have a very important property which UV lacks – the ability to provide a residual level of disinfectant in the pool water contained within the tank itself. This means chlorine/bromine can remain in the pool water actively attacking pathogens at the moment they are introduced, whereas a UV system can only disinfect the water that passes through the UV chamber within the pools recirculation system. Once the water has left the chamber, it is vulnerable to be re-infected by swimmers.
UV systems are particularly suited to both chloramine destruction and disinfection. The resulting effect is a cleaner, healthier, and more pleasant atmosphere both in and around the pool. The potential dangers caused by Trichloramines are significantly reduced, and the danger of infection by harmful microorganisms is also eliminated.
There are a variety of considerations to be taken into account when choosing an Ultra Violet system and different lamps are used in different applications. The nature of the decision can be quite detailed, making it important to find the right swimming pool professional who can assist in finding the right application for you and your aquatic facility.
As swimmers, swimming pool operators, or facility owners, we are subjected to countless myths and legends that have been floating around the aquatic community for years. These wives tales can lead to misunderstandings, and for operators, can lead to the improper care of your swimming pool. It is important to be aware of the myths, lies, and assumptions, as well as understanding the truths in order to do our part in maintaining a comfortable swimming environment for all. Here’s a list of some of the top 3 myths affecting swimmers, and operators!
"CHLORINE WILL TURN MY HAIR GREEN!"
Although believed to be the causing factor by many, chlorine is not responsible for hair discolouring. If a swimming pool has caused your hair to turn green, it is likely due to the presence of copper in the water. Metal plumbing or algaecide can cause copper to reside in the pool water.
"CHLORINE MAKES MY EYES RED AND SORE!"
We have all experienced irritated eyes and skin after swimming, and likely we have all deduced that our eyes sting and our skin is dry because there was too much chlorine in the swimming pool. Unfortunately, we have been misguided.
Swimmer “red eye” is actually caused by chloramines which are formed when nitrogen (found in urine and sweat) is combined with chlorine. These chloramines are to blame for irritating our eyes, skin and even our respiratory systems. In fact, if these chloramines exist, operators may very well need to add MORE chlorine to the pool water in order to reduce the formation of chloramines. If the pH is too low or too high, swimmers may also feel some discomfort and irritation. Human tear ducts have a pH of 7.5, which means operators must ensure the pH remains between 7.4 and 7.6 and the combined chlorine stays at 0.2ppm or below in order to maintain a comfortable swimming environment.
"THE POOL MUST BE CLEAN BECAUSE I CAN SMELL THE CHLORINE!"
When you walk into an aquatic centre and you smell the strong scent of chlorine, our automatic response is to assume it must mean the pool is clean! Maybe we relate it to the smells of cleaning chemicals, but whatever the reason, this idea is wrong. It is actually the opposite; a properly cleaned swimming pool should not smell like a chemical factory. The strong smell that we have all experienced so many times is really due to chloramines – the result of a reaction caused by the mixing of chlorine and contaminants carried into the water by swimmers.
These contaminants can include but are not limited to:
A strong smelling swimming pool can indicate that the chlorine is working harder than necessary, due to the presence of contaminants in the pool and may really mean that the pool is in need of further chemical intervention.
Pool water filtration is one of the most important aspects of a swimming pool. For obvious reasons, it is imperative that the water be clean and clear. Swimmers and lifeguards require this crystal clear water for several reasons, whether it be for swimming laps, knowing when to start a flip turn, or being able to see all of the pool patrons clearly in order to effectively monitor the pool. Furthermore, the water needs to be clean and free of bacteria so that swimmers do not leave with an illness. While there are many systems that work in conjunction with a pool filter to help keep the water healthy, the physical pool filter, which is available in varying styles and options, is the focal point in providing clean, clear water.
In most cases, pool water is pushed by the filtration pump through the filter system. Other systems operate using the pump on the other end of the system where it can pull the pool water through the filtering system. Either way, what happens is essentially the same – as water passes through the filter media, physical dirt and bacteria are removed, and clean water continues from the filter through the remainder of the recirculation system for further treatment, and returned to the pool.
The style of filter, along with the media being used, will determine the effectivness of the filtration system, as differing types of filter media actually filter different sizes of particles out of the water.
#20 SILICA SAND
The reason that pool filters use #20 silica sand (also known as 20 grit or 20 grain, 0.45-0.55 mm sized granules) is that it is small enough to filter out micro bacteria, yet large enough that it doesn’t get pushed through the whole plumbing system and cause other problems. In addition, larger granules are unable to filter the small bits of dirt and bacteria that it is intended to. #20 silica sand can filter out particles down to 20-40 microns in size. As water passes through the sand (which is essentially a really small stone, which is jagged on all edges if looked at through a microscope), the jagged edges catch tiny dirt and bacteria particles, eliminating them from the pool environment.
Depending on various factors (bather load, bather cleanliness, etc.) sand filters need to be backwashed every so often to clean the sand. If the sand filter is not maintained, it will stop filtering as it is supposed to. Backwashing is completed by running water through the system backwards to release all of the dirt and bacteria that has been caught by the sand, and must then be removed from the filter tank. When the water being discharged is clear, you are finished backwashing. Most filters have a sight glass so operators can physically see the dirty water at the beginning of backwashing eventually turn clear when the process is done.
Sand is the oldest and most commonly used filtration media, because it is effective and one of the most cost friendly options. However, after many cycles of filtering and backwashing, the granules become rounded, eliminating their filtering capabilities. The sand should be changed approximately every 5 years, depending on usage and backwashing frequency.
Zeolite is an all-natural product that is gaining popularity in the pool industry. It is about half as dense as #20 sand, meaning you can use about half as much as what is recommended for the filter. For example, if your filter requires 100 lbs. of sand, you would only require about 50 lbs. of zeolite. This type of filtration media is a bit more expensive than sand, so there will be a higher upfront cost. With the ability to filter particles down to 5 microns, Zeolite is comparable to a D.E. filter, and better than sand, though D.E. filtration systems are much more expensive than a sand filter system charged with a zeolite media. Zeolite lasts about the same amount of time as sand with regular use, which is approximately 5 years.
Crushed glass is a new addition to the filter media family. Made from recycled glass (good for the environment) that is crushed to the same size as #20 sand, it filters using the same principles as sand. In comparision to sand, crush glass lasts longer (approximately 10 years) and can help in removing micro particles with its negative charge. When using crushed glass, more of the filter media is used for filtering because it utilizes more of the filter tank, as opposed to sand which typically only uses the top four to six inches. This means there is a shorter backwash time, saving more precious water.
DIATOMACEOUS EARTH (D.E.)
Diatomaceous Earth (D.E.) filters the water very effectively, down to two to six microns, however they are more expensive systems and take up a larger footprint in the mechanical room. D.E. is tiny fossilized skeletons of sea plankton that are coated onto a grid of filter elements that sit in a tank where the pool water passes through. The water can either be pushed or pulled through this system. D.E. is considered carcinogenic, and proper handling and storage techniques, including protective gear and breathing protection, must be adhered to. D.E. filters are able to be backwashed for cleaning, but the media is lost in the process, and needs to be periodically replaced. D.E. systems do not eliminate chloramines which cause the chlorine smell commonly noticed at an indoor pool, so using a UV system is strongly recommended in order to eliminate them (a reccommendation for all pool filters).
Regenerative filters are another new option in the pool market. They also utilize D.E. or a synthetic substitute, however are a bit more complex in their design. In a traditional D.E. filter, only the channels and depressions of the surface of the filter media trap particles. The underside of the D.E., the side attached to the grid, has a reduced ability to filter. In a regenerative filter, the media is held on multiple tubes, or “fingers”, that are periodically “bumped”, causing the filter media to fall to the bottom of the tank. The filter media is then redistributed, allowing unused sides of the media to be used for filtration as well. Regenerative filters offer a large amount of surface area with a relatively small footprint and are often toted for their water saving qualities due to the reduced need for backwashing and D.E. replacement. The water savings may or may not offset the cost of these units, therefore your individual return on investment should be evaluated before purchase.
Thanks to several innovations and advancements in technology, there are many options available when considering pool filters, and filtration media. It is important to consider all of the factors specific to your project when choosing a filtration system, or to at least understand what you want and don’t want when planning with the pool designer that is working on your project. You want to have the right filtration system and media for the facility to ensure it is operating in the most economical way.
Today, technology is all around us. It makes our lives easier and allows us to connect to anything from anywhere at anytime. Having a smart phone, access to the internet, and heck - even a personal computer, is a staple in this day and age. The internet is about to become classified as a utility because we are so dependent on it for our everyday life. When I was growing up, technology was nowhere near where it is today. There was no such thing as an iPhone, an Android phone, or a Blackberry. I remember the days when a telephone was attached to the wall, it had a rotary dial and a cord, and it meant running half way across the house to answer it when someone called! The extent of modern technology in my house as a kid was a microwave, a television, a VCR and an Atari game system. If I wanted to communicate with friends I had to either call them on the old rotary phone or walk down the street to their house.
Fast forward to 2016 and just imagine your life without technology. With app’s like Twitter, all of the day’s news is waiting for us in the palm of our hand each morning. With Facebook and Instagram, we don’t even need to call our friends to know what’s happening in their lives. Technology has so much to offer and it has reached out into most areas of our everyday lives making completing daunting tasks more efficient and less time consuming. If you look around, how many people do you see without a form of technology, whether it be a mobile phone, a tablet or a personal computer?
Well the modern day swimming pool is no different. Technology, automation, and computer controls play a very important role in today’s pools. Gone are the days of having to manually adjust the chemistry in a swimming pool by hand on a regular basis. Swings and spikes in pool chemistry were difficult to control when adjusting manually, but with the help of technology, computer controls keep the chemistry in check and allow your pool to virtually run on auto pilot.
These improved chemical controllers also add an additional level of safety to the modern pool. Given that the chemical controller controls the feed of chemicals into the system, it also has the ability to lock out the feed if chemical levels get to high or too low. For example, if the PH level in a pool drops too low, the water will become very acidic and can cause damage to the pool/spa, and can also cause irritation to a swimmers body. If the body of water is very small, such as in a spa, and PH levels are drastically low, it can even cause acid burns. When the controller sees a low PH condition it will put the controller into alarm and prevent additional feeding of muriatic acid, keeping bathers safe and alerting the operator through on screen displays, texts or email notifications. The controller can also do the same thing when it comes to chlorine levels. If the chlorine levels in a pool or spa become too high, it can lock out the chlorine feed until the levels come within an acceptable range. The controllers can be set to a proportional feed, pumping in smaller amounts of chemicals to prevent “over shooting” or “spiking” chemical feed.
Behind the scenes of every swimming pool is a mechanical room; the mission control of a pool. The mechanical room is full of pumps, filters, piping, heaters, controls, UV’s, and a small computer control center called the chemical controller. The chemical controller is the brain of the entire operation, but what does it do and what are the differences between the different manufacturers?
The chemical controller constantly monitors the water through a sample line and sample cell which is fed water via the filter pump. The basic controller is checking the chlorine or bromine levels and PH with ORP and PH probes. Higher end controllers also have the ability to check free chlorine, total chlorine and stabilizer levels. What’s more, they can also connect to and control UV units, start and stop filtration systems, automatically control backwashing of the filters and they can even communicate with variable frequency drives (VFD’s) and building automation systems.
The days of worrying about your pool while you’re off duty or away from your facility are long gone. With new technology, most chemical controllers now have the ability to send a text or email notification directly to your smart phone if the controller senses a problem! You can even connect to them over the internet through HTML or smart phone apps to monitor and control the complete system from anywhere in the world. Talk about a technological advancement for a swimming pool!
Imagine being a pool operator of a commercial facility and having an issue with the pool in the middle of the night, or worse, while you are away on vacation. You could come back to a real mess, and the pool chemistry could be completely out of balance. Depending on the size of the pool, this mess could take a couple of days to get back inline. A pool with a modern chemical controller will notify you of the problem and then automatically start to chemically treat the water to keep it in balance, before you come back to a big mess.
But what are the big differences between different manufacturers? Is one better than the other? In my opinion, there really aren’t any “big” differences; they all come down to budget, options, and operator preference. All name brand controllers come with the basic ORP and PH monitors and controls, and just like a new car you can get them with options. For example; if monitoring the chlorine levels and bromine levels by ORP is not your thing, add on a PPM probe. Some operators are not familiar with ORP levels, but they are very familiar with PPM levels because this is what they commonly record in their books. Is the ability to log in and control your pool using your smart phone from anywhere in the world important to you? No problem! Just add an HTML interface. Today, most chemical controller manufacturers are seeing the importance of being connected all the time and this option is now becoming a standard hardware option and just requires setup at the time of commissioning. Are you looking to monitor the cyanuric acid level of your outdoor pool? No problem! Simply add on the probe. Free chlorine and total chlorine are an easy add-on to any system with the simple addition of monitor probes. All of these options can be added to any chemical controller.
No matter what brand you choose, at the end of the day all will ultimately do the same thing. How much it will do depends on how much you want to invest and what options you want to include.
So next time you are staying up to date with your friends on Twitter and Facebook, or checking the news on your CNN app, take a few minutes to click the pool app on your phone and see how things are operating on your swimming pool.
Water Chemistry is a significant part of the operation of your pool. Maintaining proper water chemistry in your pool will not only ensure the safety of your bathers, but also can increase the longevity of your entire pool system.
There are five chemical parameters that need to be monitored, in addition to the oxidiser used to keep the pool clean and balanced. The oxidiser, or disinfectant, is used to destroy impurities in the water, helping maintain a safe, clean swimming environment. The five chemical parameters all have inverse relationships and all impact the overall water environment in very different ways. It’s important, as a pool operator, that these parameters are carefully monitored, and adjusted when needed, to be kept within the Ontario Health Code requirements, as well as to ensure the adjustments don’t throw the other levels out of range.
pH levels and total alkalinity are two chemical parameters who work together, and can even be thought of as the best friends of water chemistry. Like most friendships, when treated properly (or balanced in this case), the friendship grows and strengthens, but if one friend is not being considered (pH or total alkalinity), the relationship can become sour quickly.
pH is the single most important parameter in swimming pool water chemistry. It drastically impacts the water balance with even a slight change on the logarithmic scale. As humans, we have a pH of 7.5, so ideally our swimming pools pH level should be maintained within the 7.4-7.6 range. pH is a measure of hydrogen ion concentration in the water, and is measured on a scale of 0-14 with 7 being the neutral pH.
What Happens when pH Levels are too Low?
When the pH is below 7.2, it is considered to be too low. At this level, the water becomes acidic, and the oxidizer decreases in strength. This will cause eye irritation for bathers, etching of the plaster walls, corroding of metal parts, staining of walls from dissolved minerals, and a significant decrease in alkalinity.
What Happens when pH Levels are too High?
pH is considered to be too high when it reaches 8 and over. High levels of pH can cause your water to become basic, can cause the oxidizer activity to slow and become inefficient, can increase scale formation and discolouration of the pool walls, and can create cloudy water causing your mechanical system to work harder to maintain a clear water environment.
One of the most common operator errors in balancing the pool water is correcting the pH without testing and balancing alkalinity. pH is the most important parameter, and has the largest impact, however, if pH’s best friend, alkalinity, isn’t monitored and balanced, the pH will never be within the proper range.
Total alkalinity is the measure of a solution’s ability to neutralize hydrogen ions expressed in parts per million (ppm), which is a measure of the water’s resistance to change in pH. The chemical used to balance alkalinity is Sodium Bicarbonate (baking soda) and the chemical used to decrease alkalinity is an Acid. If the alkalinity is within its required range (80pp-120ppm) it allows the pH to resist change and maintain its level.
What Happens when the Alkalinity Levels are too Low?
When alkalinity levels are too low, getting an accurate pH reading will be impossible Low levels of alkalinity will also create a very acidic pool environment for your bathers. The pH will change rapidly and maintain an acidic environment until the alkalinity is balanced. Once this is complete, the pH can be balanced.
What Happens when the Alkalinity Levels are too High?
If the alkalinity is too high, the pH is not truly reflective of its level and will began to bounce
(7.2,7.8,7.4). Once this occurs, it will throw off all other chemical levels and the water will become an unpleasant environment for bathers. The alkalinity MUST be within its desired range before balancing the pH levels. It is also important to let the alkalinity stabilize before any other levels are touched.
Understanding and monitoring the relationship between these two very important chemical parameters will help decrease issues in the overall chemistry of the pool. It’s important to remember that any time you are adding a specific chemical to the pool, you must be aware of and account for all other chemical levels, including how they will react to one another, and how they will affect the overall comfort and health of your pool water.
Salt Water Chlorination: Is it the Right Option for your Facility?
Wednesday, March 14, 2018
Salt or no salt? That is the question! Or at least one of the most common questions being asked by pool owners and operators these days. Every pool owner has their own set of reasons for wanting salt or not wanting salt. There are many questions regarding the mechanical equipment at the facility, finishes of the pool, uses of the pool, local bylaws, (just to name a few) that must be answered before jumping to any decisions. Additionally, the owner must be aware of the many myths regarding salt water systems and chlorine systems alike before making any decisions. They must also understand that a salt water pool doesn’t mean you will be swimming in ocean water! Windows to the Universe team states that salt water pools typically have 3,000 to 6,000 ppm, while the ocean is about 35,000 ppm.
When changing a liquid chlorine sanitized pool over to a salt water system, or when building a pool destined to be salt water, the mechanical systems must be selected properly. Everything from the pumps, filters and heaters must be designed and approved for use in a salt water pool. If this is not done, manufacturers will not honour warranties, and there will be damaged equipment much prior to their normal lifetime.
The finishes of the pool need to be considered when contemplating a salt water pool as certain finishes do not last as long under salt water conditions. Liners, tile and plaster finishes all have their own issues when it comes to salt, so owners must investigate each option thoroughly and ensure whichever option is chosen is installed properly. As with any sanitation system, monitoring and proper balancing is also very crucial in the lifetime of the finishes.
Fixtures such as hand rails, underwater lighting fixtures, and rope anchors need to be properly chosen when going with a salt water pool as they will corrode faster without being constructed of proper materials and properly maintained. The image above shows a hand rail in a salt water pool that is rusting due to the salt. Think of what salt use on our roads does to our vehicles and infrastructure during the winter months. The same type of damage will happen to a pool that doesn’t have all of its components designed for salt water use.
Primary uses of the pool under consideration for salt water should also be considered. A pool that is primarily for lap and competition swimming where there is high swimmer volume and high exertion may want to shy away from a salt system, as it will require much more monitoring of the chlorine levels to ensure they are in accepted ranges. Yes I said chlorine. Salt water pools still have chlorine in them. They use a chlorine generator system involving a process called electrolysis to produce its own chlorine, rather than adding liquid chlorine directly to the water. A therapy pool with low patron turnover may be a better candidate for salt water, as it will be easier to keep the pool balanced and may increase user comfort.
Local bylaws are another very important item to look into when considering salt water in your pool. Especially for commercial pools, salt is typically not permitted to be the primary source of sanitation. Most municipalities still require salt water pools to have a secondary sanitation system installed, typically liquid or tablet chlorination. Furthermore, when draining the pool, salt (and chlorine) levels usually must be brought down to low levels in order to legally be dumped into the municipal sewage treatment system. Always check local bylaws for your stipulations prior to draining your pool.
Pool owners need to ensure that they do as much homework on salt water chlorination as necessary to ensure that they have made an informed decision. There are too many cases of owners not taking all of the necessary steps required to properly operate a salt water pool, and have a seemingly endless repair bill. As with any large expenditure, always ensure you are working with qualified pool designers and builders when constructing a new pool or doing a renovation, no matter what sanitation system you are going with.
Health inspections are actually my favorite part of my job. Not only because the project is nearing completion, but for the sense of accomplishment when the Health Inspector comes to the facility, inspects all code requirements, and provides us with a “PASS” to open to the facility to the public.
Having years of experience in construction and participating in hundreds of health Inspections, I hear a lot of the, “Why do they have all these rules?”, “We will never be able to satisfy them”. My response to these comments is simple; Let’s do what the regulations asks for and we will get the outcome we want. It does help that we have been through lots of these inspections and can be prepared for them, but just being aware of the code requirements gives anyone the ability to be successful.
Here are a few common and very important items that the Health Inspector will look for when they inspect any facility. This is just a portion of the requirements that are listed in Regulation 565 of the Health Protection and Promotions Act for Ontario.
Do you have an emergency telephone installed and in working order? Are there instructions for your staff or patrons for when an emergency call is made? If any emergency occurs within the pool area and 911 needs to be called, anyone in the pool area may pick up the emergency phone to make the call. When making that call, the 911 operator will ask questions that will need to be answered promptly. Having the emergency instructions with the facility information posted is required so that person is able to relay this information to the 911 operator.
Are all the required safety signs posted? The regulated safety signs are to ensure that your patrons know the rules of the pool, where the emergency phone is and remind them to shower before entering the pool. They also identify for the staff how many bathers can be in the pool at one time. The signs have to legible and posted at all times.
Is the required safety equipment accessible for the patrons and staff in the pool? The health regulation lists the required safety equipment that you need on hand in case of any emergencies. These items should be maintained and checked to ensure they are in working order on a regular basis. You would never want to be in an emergency situation without the proper gear.
POOL CHEMISTRY LOGS
Are your pool chemistry logs up-to-date? Is your pool chemistry within the proper parameters? Recording your pool chemistry every 2 hours can feel exhausting especially if you don’t have a machine to handle those recordings for you. It is something that the Health Inspector will expect to see being completed. The inspector will also look for the daily and monthly checks that are required for the main drain covers and GFCI’s. Always have these records accessible. Pool chemistry can change very quickly and cause your pool to be unbalanced. Unbalanced chemistry in your pool can cause harmful bacteria and infections, and needs to be adjusted as soon as the readings are taken. Ensuring you have a test kit and a stock of chemicals on hand at all times. If the chemistry needs to be adjusted it can be done promptly.
A Health Inspector is not only ensuring that your pool complies with the rules that have been set out by this governing body, but they also ensure that the Owner and the Operator of the pool understand the codes and will follow them during operation of the pool. While the pool is in operation the patrons that are using these swimming pools do so with confidence that the individuals running those facilities are complying with the municipal codes and understand how to do so. The Health Department along with the Health Regulations will ensure this. For the Owners safety as well as the patrons.