Swimming With Sharks

Here's a good article about why it's important to use a sanitizer in your swimming pool.

Swimming in a pool or spa without any sanitizer is like swimming with sharks. Life is full of risks. We need to manage those risks in our personal life plus protect the lives of our loved ones. Would you let your children swim in a pool with sharks? Of course you would not. Would you let your children swim in a pool without sanitizer such as chlorine or bromine?

What is the risk of swimming in a pool of water without sanitizer? Just three words – recreational water illnesses (RWI). People can become ill or possibly die from exposure to microorganisms such as E.Coli, Giardia, Shigella, norovirus, cryptosporidium, and Legionella bacteria. Legionella bacteria can cause Pontiac Fever if the water is swallowed and Legionnaires' disease if water vapor is inhaled. Legionnaires' disease can be very serious and can cause death in 5% to 30% of cases. This fatality rate is higher than some Ebola viruses.

According to the nature shows, sharks do not like the taste of people. They only bite people mistaking them for seals or their favorite prey. The chance of being attacked by a shark is 1 in 10,000,000 which are slightly better odd than winning a lottery. You have better odds to be struck by lightning -1 in 500,000 odds.

What are the odds of acquiring RWI’s? I really do not know. Worldwide there is an average of 50 – 70 shark attacks on humans per year. There are thousands of cases of RWI per year in the United States. In 2005, up to 4000 people were exposed to cryptosporidium at a splash pad in New York State. In 2007, Utah saw 1,049 confirmed cases of cryptosporidium — an outbreak that has prompted health officials to ban children under 5 from public swimming pools. In 2008, all 29 public swimming pools in the city of Phoenix were closed down after cryptosporidium was detected at one pool.

To be continued with the next post.

Source: Pool Genius Network

A deeper look at Alkalinity, Part Two

The reason for a maximum level of total alkalinity is due to the fact that a level higher than 180 ppm also increases the possibility of scale forming. An exacerbating factor is that higher bicarbonate alkalinity can cause a more rapid upward drift in pH, due to the gradual loss of carbon dioxide from the water. It should to be understood that an alkalinity below 60 ppm or above 180 ppm does not necessarily mean that a corrosive or a scaling condition is imminent, only that the possibility of this condition is more likely. Other water balance parameters such as pH, calcium, and temperature may be able to counterbalance the out of range alkalinity level, although this is not a recommended way of maintaining water balance.

A low total alkalinity level can be quickly corrected by the addition of sodium bicarbonate (baking soda). Sodium bicarbonate increases the alkalinity level without affecting the pH significantly. Sodium carbonate (soda ash) also increases the alkalinity, even more than sodium bicarbonate (pound for pound). However, it may also raise the pH too high.

Too high of an alkalinity level can be corrected by adding muriatic acid or dry acid (sodium bisulfate), but will take more time because the acid has to be added slowly and in small increments.

Important Note: In regards to lowering alkalinity, there is NO truth to the concept that pouring acid in one spot of the pool (the column or “slugging” method) will result in a greater reduction of alkalinity than distributing the acid evenly around a pool. No matter how acid is added to the pool, it will always have the same effect on the alkalinity, as well as the pH. When manually adding acid to a pool, it is important to always dilute the acid and trickle it into the pool by walking around the perimeter. Acid is heavier than water and will sink to the lowest area of the pool, with the potential to damage (etch) the plaster surface, as well as the equipment if drawn in by the pump system. Pool operators should never pour undiluted acid into one area of the pool.

Source: Pool Genuis Network

A Deeper Look at Alkalinity

Of all water balance parameters, “alkalinity” may be the least understood. Alkalinity is what helps maintain a proper pH (from 7.2 to 7.8), and buffers, or resists wild pH fluctuations when sanitizers or other chemicals are added to pool water.

Sanitizers, when added to water, in addition to providing chlorine, also have an acidic (acid or low pH) or an alkaline (basic or high pH) effect on the water. It is the alkalinity (primarily in its bicarbonate form) that reacts with and “absorbs” the pH-altering effect of the sanitizer. This process “buffers” the pH, but may also either add to or lower the total amount of alkalinity in the water. Adding other types of chemicals also may have an effect on pH, and those effects are also “buffered” by the alkalinity.

The APSP has established that pool water should have a minimum of 60 ppm and a maximum of 180 ppm of total alkalinity. If the total alkalinity is below 60 ppm, there may not be enough alkalinity (buffering capacity) to resist a significant pH change if an acidic or basic chemical is added. In the case of adding an acid, the pH could drop below 7.0, making the water very corrosive to pool plaster, metal fixtures and equipment, as well as being very irritating to swimmers’ eyes. In the case of adding a high pH (alkaline) chemical, the pH could go excessively high (over 8.3), which increases the likelihood of calcium carbonate (scale) depositing onto the pool surface and equipment.

Source: Pool Genuis Network