Why you need Kemio

Disinfection and sanitation with chlorine

The most common sanitizer used in food and beverage processing due to its relatively low cost and efficacy at preventing produce cross-contamination.

However, chlorine is very sensitive to pH and temperature, so both parameters must be carefully controlled to achieve optimum performance. In wash waters with high organic matter loads, an increased requirement for chlorine is demanded to ensure effective sanitization.

‘Free’ chlorine has the highest disinfection efficacy and usually exists in water as hypochlorous acid or the hypochlorite ion, with the proportion of each dependent upon the pH of the sample. ‘Total’ chlorine is the sum of free chlorine and combined chlorine (or chloramines, which have weaker disinfection properties).


  • Get repeatable and reliable results each time. Kemio minimises user input to deliver consistent results from all operators.
  • Reduce uncertainty of test results by enabling operators to act on clear pass/fail results based on your specification.
  • Kemio is suitable for all users, with clear visual instructions which requires user training. Clear visual instructions guide the user and minimises chances for error.
  • Suitable for all sample types, Kemio is not affected by coloured or turbid samples.
  • Reduce expensive laboratory tests with Kemio spot checks.
  • Measure free chlorine, combined chlorine, total chlorine, chlorine dioxide, chlorite and PAA on one instrument.
  • Personalise your Kemio by adding your unique test and application information to improve traceability and provide a complete dataset.
  • Go paperless and protect your data to meet your compliance requirements. The integrated data log summarises 10,000 results to provide a traceable, auditable dataset.
What is free chlorine?

Free chlorine has the highest disinfection efficacy and usually exists in water as hypochlorous acid (HOCl) or the hypochlorite ion (OCl – ), with the proportion of each dependent upon the pH of the sample.

What is total chlorine?

Total chlorine is the sum of free chlorine and combined chlorine, or chloramines, which have weaker disinfection properties. When chlorine comes into contact with molecules containing nitrogen, it reacts to form a chloramine. Chloramines and free chlorine together are referred to as total chlorine.

Why should I measure free chlorine?

Free chlorine and combined chlorine have different disinfection potential. Free chlorine has a stronger sanitizing potential and therefore the presence of free chlorine residual gives an indication of the sanitizing potential of your wash water. We recommend the level of free chlorine is set to ensure sufficient disinfection and must be monitored separately from total chlorine.

What level of free chlorine should I use?

This is dependent on the application for which you are using the chlorine as a sanitizer. Other factors to consider include the organic matter, the type of produce, and the contact time. Levels can range from as low as 5 mg/L to over 200 mg/L.

There are numerous methods for measuring free and total chlorine.  Our sensor technology provides precise and accurate results across a wide range of concentrations for free and total chlorine. Our sensor method has been designed specifically for food and beverage applications.

What are the disinfection by-products (DBP) of chlorine?

When chlorine interacts with natural organic matter in the water, disinfection by-products (DBP) called trihalomethanes (THM) are formed. These substances can have adverse health and environmental effects and need to be monitored.

What's the impact of diluting the wash water sample?

Methods requiring dilution introduce potential error. For example, a 1 in 100 dilution magnifies any measurement error on the 1 mg/L by 100 times. For systems with high frequency of tests, and a variation in operator experience, errors are inevitable and magnified during dilution. Our sensor method has a high range, which reduces the need for dilution.

Contact our team to find out how we can support you

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Our mission is to promote effective food and beverage safety to ensure that we can all eat and drink safely. Visit our content hub to find a number of helpful articles about food and beverage safety, sanitation control and best industry practice.


Why Kemio Technology?

Kemio technology offers significant advantages compared to alternative techniques for sanitizer control in food and beverage. Unlike traditional methods, Kemio has no user subjectivity and minimal user input which minimizes potential operator errors and variation in results.