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.
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.