Organic vs Inorganic Combined Chlorine

Jump to latest Follow Reply
B

BrandonHutson

In The Industry
Sep 13, 2024
2
Michigan
Hi,

I work at an indoor resort. We have several pools, spas, and waterslides. We occasionally have issues with high combined chlorine. Sometimes, when we treat the combined chlorine, we see no change at all.

We utilize multiple methods to treat combined chlorine (oxy-shock, breakpoint, etc), depending on what time of day it is and how busy we are.

I know that there is a difference between organic and inorganic combined chlorine, and I have been told that some of our treatment methods might not be working because we are not using the right method for the type of combined chlorine that we are dealing with at that time.

What I would like to know is, how can we figure out what type of combined chlorine we are dealing with in a specific body of water? Are there specific test kits that exist for this? Does anyone out there have a method for this? Or have I been misled, and is there a different reason for why our combined chlorine treatments are not neutralizing the combined chlorine?

Any thoughts or tips on this would be greatly appreciated. Thank you.
 
“Oxy shock” or mps can read as cc when testing if an interference reagent isn’t used. Are you using the Taylor R-0867 Deox Reagent after using mps?

@JoyfulNoise
Can likely elaborate on the organic/inorganic chemistry
 
BrandonHutson said:
No, we do not use that. I am going to order some though. Thanks.
Click to expand...
That may solve your mystery- not a question of whether the cc’s are organic or inorganic. Because I really don’t think that matters.
Perhaps you’re just seeing false cc results due to the mps.
 
  • Like
Reactions: Bperry
Organics are based on carbon and inorganic are based on non carbon atoms like nitrogen.

In swimming pools, organic chloramines form when chlorine reacts with organic matter, and these chloramines can lead to trihalomethane (THM) formation, which are disinfection byproducts potentially harmful to humans.

When chlorine bonds to ammonia, it tries to oxidize the nitrogen by removing electrons, but the nitrogen holds on to the electrons and it is a slow process.

UV light is absorbed by the electrons and gives them enough energy to move from the nitrogen to the chlorine causing the nitrogen to convert into nitrogen gas and the chlorine to become chloride.

4NH3 + 3HOCl + 3OCl- --> 2NClH2+ 2NCl2H + 3H2O + 3OH- --> 2N2 + 6H2O + 3H+ + 6Cl-

UV in sunlight or from a UV system will oxidize chloramines.

Monchloramine 245 nanometers
Dichloramine 297 nanometers
Trichloramine 260 and 340 nanometers.

The four Trihalomethanes are:

[CHCl3] Trichloromethane (chloroform) [3 chlorines]
[CHClBr2] Dibromochloromethane [1 chlorine, 2 bromine]
[CHCl2Br] Bromodichloromethane [2 chlorine, 1 bromine]
[CHBr3] Tribromomethane [3 bromines]

The EPA's most current regulations limit the concentration of these 4 chemicals added together (total trihalomethanes, or TTHM) to 80 parts-per-billion (ppb/µg/L).

The most common in chlorinated swimming pools: chloroform.

The carbon can be oxidized to carbon dioxide with a +4 for carbon like the burning of methane.

Organics are more persistent.

For a high use indoor pool, you need a supplemental sanitization system like ozone or UV.

I would use a good commercial grade UV system.

Some places are required to use a Secondary Disinfection System according to apsp-11_2019



issuu.com

ANSI/APSP/ICC-11 2019 American National Standard for Water Quality in Public Pools and Spas

The ANSI/APSP/ICC-11 2019 American National Standard for Water Quality in Public Pools and Spas provides recommended minimum guidelines for the specifications for recreational water quality parameters in public pools and spas. An Appendix A includes explanatory sections about the values for the...
issuu.com issuu.com


1741480048753.png
1741480490586.png
1741480526344.png
The ANSI/APSP/ICC-11 2019 American National Standard for Water Quality in Public Pools and Spas provides recommended minimum guidelines for the specifications for recreational water quality parameters in public pools and spas.

An Appendix A includes explanatory sections about the values for the requirements listed in the body of the standard.

Based on health-related scientific information, this standard can be incorporated into national or regional health codes, and adopted by state and/or municipalities as a local code or ordinance.
 
  • Like
Reactions: Mdragger88
Besides chloramines, you have things like infective Cryptosporidium parvum oocysts that can pass from swimmer to swimmer.

Recreational Water Illnesses (RWIs) are infections that occur after exposure to contaminated recreational water, such as swimming pools, hot tubs, lakes, rivers, and oceans.

Bacteria (e.g., E. coli, Legionella).
Viruses (e.g., norovirus).
Parasites (e.g., Giardia, Cryptosporidium).

People who are at increased risk for RWIs include:
Young children
Older adults
People with weakened immune systems
People who swallow or breathe in contaminated water
People who have open wounds or cuts that come into contact with contaminated water

Recreational Water Illnesses (RWIs) - MN Dept. of Health

www.health.state.mn.us www.health.state.mn.us

www.cdc.gov

Preventing Swimming-related Illnesses

Learn how to prevent swimmer's ear, Crypto, hot tub rash, and other swimming-related illnesses.
www.cdc.gov www.cdc.gov

www.ewg.org

EWG’s Guide to Reducing Disinfection Byproducts in Pools

Swimming pool disinfection is essential and necessary to prevent skin recreational water illnesses like rashes and diarrhea caused by bacteria, viruses, and other parasites. But when pool chlorine and other disinfectants react with contaminants in the water, they form harmful disinfection by...
www.ewg.org www.ewg.org
 
Last edited:
  • Like
Reactions: Mdragger88
TFP is a registered 501(c)3 non-profit that is maintained by user donations.

The people who answer questions are volunteers.

If you find the site to be a good resource, please consider making a donation to help support the site.

Thanks.

www.troublefreepool.com

Become a TFP Supporter

Help Support TFP Trouble Free Pool is run by a dedicated group of volunteers that … Read more…
www.troublefreepool.com www.troublefreepool.com
 
  • Like
Reactions: Mdragger88
You must log in or register to reply here.
Top Bottom
Back
Jump to latest Follow Reply