-Yellow-green toxic gas and oxidizer

-Max allowed exposure limit1 ppm, or 3 mg/m3

-Warfare gas in WWI Chlorine Can Gain Weight

Drinking or showering in chlorinated water can have an impact on weight gain on a few fronts. As a harmful substance, chlorine removes the iodine in your thyroid, prompting hypothyroidism and undesirable symptoms like hot flashes and weight gain. What’s more, since your liver is caught up with dispensing extra estrogens, it is more resistant to work admirably performing other vital capacities like burning fat.

 “Chloriden zijn verbindingen waarin chloor in de oxidatietoestand −1 voorkomt. Het chloride-ion is het negatief geladen ion Cl. Het ontstaat wanneer een neutraal atoom van het element chloor één elektron opneemt”

Negatieve eigenschappen:

-oxiderend, roestvorming (zoals bvb in zeewater)

-ecologische effecten: zuurvorming waterlopen

-hindert denitrificatie

-alergische reacties

-afbraak natuurlijke menselijke biofilm en ‘goede bacteriën’ (zoals lactobacillus in GI tract)

-kan ook leiden tot arthritis

-kan chloroform vormen

-kan leiden tot nier,lever en zenuwstelsel problemen

Measurements needed for a good interpretation: FAC,TAC,ORP,pH,and Ammonia concentration.

Free available chlorine (FAC or free residual chlorine= hypochlorite ions (OCl-) + hypochlorous acid (HOCl))

It is the portion of chlorine that remains available for disinfection, after the chlorine reacts with compounds in the water.

A minimum free available chlorine concentration is required as it confirms there is remaining chlorine portion to prevent recontamination.

Chlorine reacts with organic/inorganic compounds, bacteria, metals, ammonia,..

Disinfection byproducts (DBPs) : Trihalomethanes (THMs)

Chlorine which reacts with ammonia (to form chloramines and causing taste and odour problems) still possesses the ability to disinfect water, but to a weaker extent.    

The mechanism of chlorine disinfection is oxidation, a process of electron transfer that can destroy biological organisms. The cell walls of bacteria hold a negative charge, which causes hypochlorite hypochloriet) ions to be repelled from the organisms, so disinfection occurs best with hypochlorous acid (waterstofhypochloriet), since it does not have the negative charge that hypochlorite ions have.

FAC depends on the pH of the water, with hypochlorous acid favouring lower pH (6.0 – 7.6), and hypochlorite ions favouring higher pH (7.6 – 10).

A pH below 7.6 is ideal for disinfection, with pH in the low-7 range typically seen at treatment plants. 

Figure 4:          Recommended chemical parameters table for swimming pools. Note the requirement for combined chlorine to be low, even though it still has disinfection power (Qld Health, 2004)

FAC measurement is followed up with total available chlorine (TAC) measurement (by the simple addition of DPD-3 to the sample)

ORP is typically measured with an ORP probe that contains an ORP electrode (gaining electrons) and a reference electrode, similar to how pH is measured.

Higher ORP values correlate with faster kill times of micro-organisms.

Drinking water redox potential: 650 mV

Swimming pool redox potential: 700 – 750 mV

Ref. MEASURING THE POWER OF DISINFECTION: WHAT YOU NEED TO KNOW, Mario Ruckli, Graduate Engineer, Simmonds & Bristow


(Recommended 4–6 mg/L with shock dose of 10 mg/L)

Bromine can be used as a disinfectant alternative for chlorine, especially in spas and hot tubs. The bromamines which are formed when bromine is added to pool or spa water are as effective as free chlorine in killing pathogenic microorganisms, therefore total bromine is the key parameter to monitor.


Ozone is also used as a primary disinfectant and must be sufficiently dissolved into the pool water to carry out the required oxidation and disinfection. Although ozone is a powerful disinfectant, adequate residuals of ozone must be maintained in the pool water to ensure full control. It is very often used with chlorine or bromine as a secondary disinfectant due to the difficulty in maintaining constant residual.

Ozone can purify water 3000 times faster than chlorine. It is also very effective at killing Cryptosporidium and Giardia which are unaffected by chlorine disinfection.

Ozone use does not affect the pH level of the pool. It does have a large initial cost, but when using ozone, the free chlorine levels can be much lower (0.5 mg/L for a pool, and 2–3 mg/L in spas and hydrotherapypools).


PHMB is an alternative disinfectant to chlorine or bromine and is used in conjunction with a hydrogen peroxide disinfectant regime. The recommended levels for PHMB are 20–40

mg/L, however, this will vary with exact pool temperatures and location.

Hydrogen Peroxide

Hydrogen peroxide cannot be used as the only disinfectant in pools because it breaks down too

quickly. It can enhance the disinfectant power of other oxidisers such as chlorine, UV or ozone

treatments. The recommended levels will vary according to the size of your pool and the local authority, but typically a level of 30–100 mg/L is required in a peroxide treated pool.

Alternatief: Chloordioxide (onsite production using 2 components: natriumchloriet + zuur)

Omzetting ClO2->chlorite->chlorate

Lagere ORP dan waterstofhypochloriet

Een effectief ontsmettingsmiddel (oxidant en biocide) bij lage concentraties

Vormt weinig bijproduct

10x meer oplosbaar in water

Is effectief bij Ph 6 tot 9

EU DWGL 98/83 limit : 0.2 ppm in drinkingwater, minimaal corrosief effect in deze dosering

EPA : max. 0.8 ppm in drinkingwater

Reageert minder met organische producten dan Chloor, minder schadelijke bijproducten

Bij concentratie boven 10% -> explosief

Zeer effectief in zure omgeving

Effectief om biofilm te verwijderen

Alternatief: electrochemical technologies

EU Goedkeuring sinds 03/03/2021

actief chloor, door middel van elektrolyse verkregen uit natriumchloride PT2, 3, 4 en 5.

actief chloor, door middel van elektrolyse verkregen uit natriumchloride PT1

Cel membraan elektrolyse technologie (met ion selectieve membranen)

History :1851 & 1853 – Cook and Watt obtained patents for electrolysis of chlorine from brine.


In-situ productie van desinfecterend gas (via buffertank en recirculatie)

15g/h 15amp unit (0,3kW), geeft 1ppm chloorgas per uur in buffertank van 15m³

30 g/h 30Amp (0,6kW), geeft 2ppm vrij chloor per uur in buffertank van 15m³

Enkel werkzame bestanddelen komen in contact met het water

Waterontharder is nodig bij hardheid >4-6F°. Profine Ocra | Profine (

Enkel productie als het nodig is (via regeling geen gasoverschot=veiliger)

->gebruik van goedgekeurd Marina Esco elektrolyse zout

->geen corrosief water, enkel zacht

->geen zoutsluier of zout smaak

->geen chloorgeur

->geen stockage of transport van vloeibaar chloor

->geen residuen in het water

->AguaCon: Modulerend meetsysteem (pH en Redox): voor pH- en Redoxwaarde en proportionele aansturing met internet aansluiting mogelijkheid.

->Wallace & Tiernan meetsysteem (pH en vrij chloor) en proportionele aansturing met internet aansluiting mogelijkheid.


-zwembaden, whirlpools,spa´s, fonteinen, sierteelt, slateelt, ijsblokken behandeling,… (niet voor waters met vissen!)

Interne prijzen excl. BTW: (marge 30-40%)

-Aguapure 100 NC 15A (1 cel – 15 gram/u) met sturing en met kleur touchscreen:€ 6.945

-Aguapure 200 NC 30A (2 cellen – 30 gram/u) met sturingskast en met kleur touchscreen:€ 8.990

-AguaTra: AAN/UIT meetsysteem (pH en Redox):€ 1.045

-AguaCon: Modulerend meetsysteem (pH en Redox):€ 1.723

-Wallace & Tiernan meetsysteem (pH en vrij chloor):€ 4.230

-Optie internet package:€ 309

-De Aguapure 5, bestemd voor particulier gebruik voor het desinfecteren van een regenput of voor een jacuzzi, is in zijn laatste ontwikkelingsfase, waarbij je mag rekenen op een prijs van 3000 euro excl. btw voor het toestel met bijhorende sturingskast.

-Periodieke onderhoudskosten: wij raden elke 2 jaar een onderhoud aan van de cel (+/- 1 werkuur):

-Anode: € 138,50

-Kathode: € 126,40

-Selectief membraan: € 128,60

In addition to the EPA water regulation there are  Secondary Drinking Water Regulations (NSDWRs) that set non-mandatory water quality standards for 15 contaminants. EPA does not enforce these “secondary maximum contaminant levels” (SMCLs). They are established as guidelines to assist public water systems in managing their drinking water for aesthetic considerations, such as taste, color, and odor. These contaminants are not considered to present a risk to human health at the SMCL.

The problems of the secondary contaminants are

Aesthetic effects — undesirable tastes or odors;

Cosmetic effects — effects which do not damage the body but are still undesirable

Technical effects — damage to water equipment or reduced effectiveness of treatment for other contaminants

The SMCLs related to each of these effects are shown in the table below.

PT 2     Desinfecteermiddelen en algiciden die niet rechtstreeks op mens of dier worden gebruikt

->gebruik voor zwembaden en bubbelbaden.

1160 goedgekeurde producten

30tal tijdelijke toelatingen: Algemene tijdelijke toelatingsakte, Producten PT 2 gebruik, (artikel 55 (1) BPR)

Search PT2 : Belgium list, all products

  • Chlorine:

Active substance to kill germs is free chlorine, CDC recommends pH 7.2–7.8 and free chlorine 1ppm to max 3ppm (ex. jacuzzi)

-as pH increases -> ability of free chlorine to kill germs decreases (especially when pH is >8.0)

-as pH goes down -> ability of free chlorine to kill germs increases, but the pool or hot tub/spa pipes are more likely to corrode or break down. (especially if pH is <7.0)

-pH between 7.2–7.8 -> comfortable for swimming -> prevent eye and skin irritation.

Free Available Chlorine Germ-Killing Timetable

E. coli 0157:H7 (Bacterium)      less than 1 minute

Hepatitis A (Virus)        approximately 16 minutes

Giardia (Parasite)          approximately 45 minutes

Cryptosporidium (Parasite)        approximately 15,300 minutes (10.6 days)

Cyanuric acid (cyaanzuur) is used as a chlorine stabilizer (products: dichlor, trichlor,..)

Recommended use by Ph 7,2-7,6 (

Concentratie cyaanzuur moet < 20 mg/L zijn. >70 mg/L = probleem

Chloortabletten : Symcloseen, Trichloro-1,3,5-2,4,6-trione, Trichloorisocyanuurzuur

Chloorgranulaten : bevatten Natriumdichloorisocyanuraat, de stof is irriterend voor de ogen, de huid en de luchtwegen. Herhaald of langdurig huidcontact kan een huidontsteking veroorzaken.

It is considered hazardous according to OSHA 29 CFR 1910.1200. High level exposure can cause reactive airways dysfunction syndrome (RADS)

->reduces effectiveness, less desinfective but longer lasting tablets

->but to be avoided


Chloor vloeibaar BE-REG-00358 20 L (Chloorbleekloog), Natriumhypochloriet (UN 1791)

Dosering zwembadwater: 8ml/m³ = 1ppm actieve chloor, bevat 13% actief chloor.


  • Copper-Silver

Bifipro® systeem          HOLLAND WATER B.V.        NOTIF835

PT 5 – Drinking water disinfectants, PT 11 – Preservatives for liquid-cooling and processing systems

Koper (CAS 7440-50-8): 200 -1000 µg/l

Zilver (CAS 7440-22-4): 10 – 50 µg/l

Professional & Free circuit, 0.20 ppm Copper, 0.01ppm Silver, valid until 31/12/2024