Authored By: Zachary Waszczak
Ozone (O3) is commonly used in many industries for sanitation and disinfection purposes. It is often necessary to measure residual ozone to ensure proper sanitation and product control. For this purpose, there are many choices for ozone test kits currently available and choosing the correct one will keep your workflow fast and accurate. To choose the right test kit, consider your application, your testing range, and any possible interferences.
Common Uses for Ozone Test Kits
Ozone is a strong oxidizing agent used for disinfection and sanitation. It is growing in popularity as ozone use does not lead to harmful disinfection by products (DBP). While it is used in many industries, two of the largest applications are the dairy and bottled water industries.
Ozone is frequently utilized in dairies where water is ozonated and used to clean surfaces involved in milking and food production. The use of O3 in this application prevents mold without affecting the odor or taste of the finished product. Ozone test kits are used to ensure that the water is properly ozonated so it can safely clean the surfaces without degrading equipment or product quality.
In the production of bottled water, ozone is added to the water just before filling the bottles. The concentration of ozone is carefully balanced to be high enough to kill any harmful organisms but low enough that it is not noticed by the consumer when the bottle is opened.
Consider Your Application
The first step in choosing the best ozone test kit is to consider what you are measuring. Are you measuring a cleaning solution, your actual product, or something else? Do you need a device with a digital read out or are visual readings acceptable? Are you testing in a lab or quality facility or directly in the field? All of these questions will guide your purchasing decision and help you find the optimal test kit.
Remember Your Testing Range
Once you know what features you are looking for, you need to consider your testing range. Ozone in water is commonly measured in parts per million (ppm), also known as mg/L. Aquaphoenix Scientific/CHEMetrics offers ozone test kits for multiple ranges. Use the table below to help you find which options apply best to your concentrations.
| Manufacturer | Product Code | Test Type | Testing Range (O3) |
| CHEMetrics | I-2019 | Instrumental | 0 – 5.00 ppm |
| CHEMetrics | I-2022 | Instrumental | 0 – 0.75 ppm |
| CHEMetrics | I-2023 | Instrumental | 0 – 0.25 ppm |
| CHEMetrics | K-7404 | Visual | 0 – 0.60 & 0.6 – 3.0 ppm |
| Hach | 2518025 | Instrumental | 0.01 – 1.50 ppm |
| SenSafe | 481234 | Visual | 0 – 0.5 ppm |
Aquaphoenix offers multiple ozone test kits that fall into 2 primary categories, visual test kits and instrumental test kits. Visual test kits are read by a reagent changing color and being compared to a chart to find your concentration. Instrumental test kits work off the same colorimetric idea, but an instrument measures the result and provides an answer. Typically, instrumental ozone test kits will provide greater precision and a larger testing range.
Do You Have Interferences?
Before purchasing your ozone test kit, ask yourself “Do I have any potential interferences?” The most common interference for a colorimetric test kit is color. If the sample being tested has background color, it will be difficult to see the color development and acquire reliable results. If your sample has a colored tint, there may be ways to troubleshoot the problem like pretreating the sample. Reach out to our technical services department for assistance.
There are two popular Ozone test kit chemistries. Depending on your potential interferences you may prefer one over the other.
Testing for Ozone with DPD
The first testing method is the N, N-diethyl-p-phenylenediamine (DPD) method. This chemistry uses potassium iodide to treat the sample so the ozone will react and liberate the iodine. The iodine then reacts with the DPD to form the pink color, which can then be measured or compared. Common contaminants for this test kit are oxidizers such as chlorine, bromine, iodine, peracetic acid, performic acid, chlorine dioxide, and permanganate. A full list of contaminants and common solutions can be found on our Technical Data Sheet.
Testing for Ozone with the Indigo Method
The Indigo method utilizes indigo trisulfonate dye that reacts with dissolved ozone in water. The test ampoules are colored blue, and the ampoule loses color rather than having the color develop in the presence of ozone. This chemistry is formulated to be resistant to at least 10 ppm chlorine, lowering the risk of interference. A full list of contaminants and troubleshooting techniques are available on our Technical Data Sheet.
AquaPhoenix Ozone Test Kits
AquaPhoenix offers a range of ozone test kits from top brands to meet your testing needs. Many of these products are in stock and ready to ship the same day. Below is a quick summary and link to the product page.
CHEMetrics Ozone Test Kits
DPD
K-7404 is a visual test that is ideal for working in the field or lab. It comes in a sturdy plastic case that contains everything you need to conduct 30 tests. It is capable of testing at low (0-0.6 ppm) and high (0.6-3.0 ppm) ozone ranges. The kit can be refilled with ampoules and testing solution for further use.
I-2019 is an instrumental test that comes with a CHEMetrics Single Analyte Meter (SAM) that reads the Vacu-vials ampoules. This kit comes with everything needed for 30 tests and can be refilled with further ampoules. Everything comes packed in a plastic case with foam inserts for convenient testing on the go. It is recommended for applications where a wider testing range is required (0 -5.00 ppm O3)
Indigo
I-2023 is a low range (0-0.25 ppm) instrumental ozone test kit from CHEMetrics. This kit is a great fit for drinking water and bottled water applications where residual concentrations of ozone will be low. The kit contains ampoules for 30 tests, a CHEMetrics SAM, and a convenient carrying case for lab or field testing.
I-2019 is CHEMetrics high range (0-0.75 ppm) instrumental ozone test kit. It is best used for applications that need accurate readings up to 0.75 ppm O3.
The video below shows how these tests can be used to test directly in a bottle of water to prevent any O3 loss.
Hach Ozone AccuVac®
Product #: 2518025 is a pack of 25 Ozone Accuvac® ampoules that utilize the Indigo method and can measure between 0.01 – 1.50 ppm O3. They require a Hach instrument capable of accepting AccuVac® ampoules.
SenSafe Ozone Test Strips
Product #: 481234 are SenSafe test strips are a fast and easy way to measure between 0-0.50 ppm O3 offering results in 30 seconds. These strips are mostly used in drinking water, pools, spas, or industrial process water and offer a quick and reliable way to check for the presence of ozone.
Shopping for Ozone Test Kits
There are many different chemistries, ranges and product lines available to technicians looking for an ozone test kit. Fortunately, AquaPhoenix offers easy ordering for all the top brands with many products having same day shipping. Should you need further assistance or have any questions please reach out to our customer support team.