Ozone Test Kits
Visual Kit
Range | MDL | Method | Type | Test Kit | Refill |
---|---|---|---|---|---|
0.0 - 0.6 & 0.6 - 3.0 ppm | 0.025 ppm | DPD | CHEMets | K-7404 | R-7404 |
Instrumental Kits
Range | Method | Type | Test Kit | SAM Kit |
---|---|---|---|---|
0 - 0.25 ppm | Indigo | Vacu-vials | K-7453 | I-2023 |
0 - 0.75 ppm | Indigo | Vacu-vials | K-7433 | I-2022 |
0 - 5.00 ppm | DPD | Vacu-vials | K-7423 | I-2019 |
The CHEMetrics test kits for the determination of Ozone in aqueous solutions are based on patented Self-Filling Reagent Ampoule technology, and employ the DPD and Indigo methods. Premixed. Premeasured. Precise. Each kit contains 30 tests. Suitable for industrial water testing as well as food safety and aseptic bottling testing. Indigo is the method of choice for bottled water applications.
CHEMetrics visual ozone DPD test kit features CHEMets® self-filling ampoules that contain pre-measured reagent for a single test. Simply snap the ampoule directly in a sample to draw in the correct volume of sample and then compare to the supplied colour standards to find the concentration.
Instrumental Vacu-vials® ozone kits feature a 13mm diameter ampoule, utilise the same self-filling technology as CHEMets and are available with both DPD and Indigo methods. Unlike other ozone test kits, the Indigo Vacu-vials kits feature a self-zeroing chemistry that eliminates the need to generate an initial zeroing ampoule each time a test is run. Only one ampoule is needed for each O3 water test, meaning cost savings for you!
Ozone Vacu-vials kits rely on CHEMetrics direct-readout photometers or spectrophotometers capable of accepting a 13-mm diameter round cell. CHEMetrics offers two Single Analyte Meter kits, the I-2023 and I-2022, specifically designed for use with the K-7453 and K-7433 ampoules, to provide automatic self-zeroing calculation and direct reading of the results. The Ozone DPD Vacu-vials test kit K-7423 can also be used with a Hach DR900 Colorimeter in conjunction with the CHEMetrics DR900 Vacu-vials® Adapter, Cat. No. A-0215. No endorsement by Hach Company is implied or intended.
DPD Method
Potassium iodide is added to the sample before analysis. Ozone reacts with the iodide to liberate iodine. The iodine reacts with DPD (N, N-diethyl-p-phenylenediamine) to form a pink colour. Results are expressed as ppm (mg/l) O3.
References:
USEPA Methods for Chemical Analysis of Water and Wastes, Method 330.5 (1983).
APHA Standard Methods, 22nd ed., Method 4500-Cl G- 2000.
Technical Data Sheet |
Technical Bulletin: Determination of Ozone Concentration in the Presence of Chlorine |
Indigo Method
The indigo trisulphonate method uses a blue dye which fades in the presence of ozone. The indigo method is specified in the US National Primary Drinking Water Regulations (NPDWR) so it is the method of choice for many water bottling operations.
With the indigo method, indigo trisulphonate dye immediately reacts with ozone. The colour of the blue dye decreases in intensity in proportion to the amount of ozone present in the sample. The test reagent is formulated with malonic acid to prevent interference from up to at least 10 ppm chlorine. Results are expressed as ppm (mg/l) O3.
The CHEMetrics Indigo Ozone Vacu-vials® Kit employs an innovative "self-zeroing" feature to eliminate the need to generate a reagent blank. Each Vacu-vials® ampoule is measured before and after being snapped in sample. The change in colour intensity, measured in absorbance between reagent in the unsnapped and snapped ampoule is used to determine the ozone concentration of the sample. Only one ampoule is required per test, meaning shorter testing times, greater efficiency and cost savings.
The Indigo Vacu-vials kit is compatible with a number of different spectrophotometers that accept a 13 mm diameter round cell, and with a 'Z dimension' of 15mm or less (because of the self-zeroing feature).
Click here for more information on CHEMetrics Ozone Indigo test kits and bottle water testing, and an Ozone Indigo product comparison.
References:
Bader H. and J. Hoigné, "Determination of Ozone in Water by the Indigo Method," Water Research Vol. 15, pp. 449-456, 1981.
APHA Standard Methods, 22nd ed., Method 4500-03 B (1997).
Technical Data Sheet |
Applications
Ozone's mechanism of action is to destroy microorganisms through oxidation, for which microorganisms cannot build up a resistive tolerance to, as opposed to systematic poisoning. Ozone is a broad-spectrum biocide and can help to control algae and other aquatic growths. It is often used as a disinfectant in a wide range of processes such as viral, bacterial and parasitic disinfection. Ozone is used in a variety of industries and processes, including air and water purification, deodourisation, decolourisation, food safety, bottled water industry, winery and brewery sanitation (barrel/tank cleaning), pharmaceutical industries, aquaculture (nitrite oxidation), pools and spas, groundwater remediation, electronics (surface cleaning), cooling water towers, laundry, and general industrial wastewater treatment. Ozone is also used to oxidize inorganic impurities such as iron, manganese and sulfides and has been shown to improve wastewater treatment coagulation processes.
If it is being used as a disinfectant, O3 water testing is critical to ensure that the concentration is high enough to remove harmful agents. Excess disinfectant is costly and, when used for drinking water disinfection, can itself affect odor and taste. Frequent testing of the concentration of dissolved ozone in water keeps systems running at peak efficiency.
Drinking Water
Ozone can be used in water to remove taste, odour and colour-affecting compounds. Ozone can be used as an alternative to chlorine, as a broad-spectrum biocide, disinfectant and steriliser. After ozonation of water, no regrowth of harmful microorganisms occurs, except where they are protected by wastewater particulates. Ozonation is more costly than chlorination. However, ozone has increased in popularity as a water treatment method as regulatory limits for allowable concentrations of disinfection byproducts (DBPs), such as trihalomethanes (THMs) and haloacetic acids (HAAs), have become more challenging for municipalities to meet. Ozone can reduce DBPs in two ways:
- When used as either a pre-oxidant or as the primary disinfectant, it can significantly lower the amount of chlorine required as a secondary disinfectant in the distribution system.
- When ozone is used in conjunction with biologically active filters, it can significantly reduce the amount of organic material available to be chlorinated which helps to limit DBP formation.
Bottled Water & Aseptic Packaging
One of the advantages of ozone is that it breaks down to oxygen within a short period of time leaving no residual chemicals or contaminants. Its use therefore does not require additional rinsing steps. It therefore has particular relevance to aseptic bottling in the bottled water industry. Water bottling facilities use ozone as the last disinfection step just prior to bottling. They must ensure a low level of ozone residual is maintained to meet regulatory limits.
What is Ozone?
Ozone (O3) is an inorganic molecule containing three oxygen atoms. It is an allotrope of oxygen (O2) although much less stable. Ozone is a pale blue gas with a distinctive chlorine-like smell and slightly soluble in water. Ozone is highly reactive and a powerful oxidising agent, much more so than Oxygen. It is found in low concentrations in the Earth's stratosphere and can be produced by electrolysis or corona discharge.