WEBVTT 

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A UV light water treatment system allows water to flow around a UV lamp, 

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inactivating bacterial cells. 

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Just like rays from the sun, 

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this concentrated UV light can be dangerous,

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so the system includes a protective case.

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The UV radiation will not have a residual impact on the water.

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Ultraviolet, or UV light, uses radiation to disinfect.

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As water passes through a tube, it’s exposed to ultraviolet light.

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When water is exposed to light for enough time, 

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microbes in the water are exposed to UV radiation.

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This changes the DNA of microbial cells, killing them.

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Because cells have to be exposed to enough light, 

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it’s important to control flow rate 

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and make sure all water is exposed for enough time.

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If water flows too quickly, UV light can’t disinfect it.

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If water is too dirty or turbid, 

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the UV light won't be able to pass through to work properly.

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Many UV systems will have an option to include a sensor that monitors how much

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UV light is passing through the water. 

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This is an important feature 

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and should be included in any treatment system 

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to verify the water is not too dirty for effective treatment.

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If the system is not self-cleaning, 

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clean the quartz glass tube regularly. 

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UV light systems don’t require a lot of maintenance, 

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but it is critical that this glass tube is clean, 

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or the light won’t reach the water properly.

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It can be hard to know if this tube is clean enough. 

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This is another reason why systems with added UV sensors 

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are highly recommended for monitoring.

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You validate the system when it is initially installed.

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Be sure to check water flow rates 

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so that water is not moving too fast.

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And also check the cloudiness or turbidity of the water

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to make sure the UV light will be effective.

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Every time the system is operated, you will need to monitor it.

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You will want to make sure that the UV sensor is 

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detecting adequate UV intensity through the water. 

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This criteria will be established by the system manufacturer 

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and is one reason why a sensor is important.

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Check to make sure the lamp is powered on, 

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and that the flow rate is set appropriately.

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Verify that your system is working as expected. 

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Observe the employee monitoring the system, 

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calibrate the UV sensor per manufacturer recommendations, 

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collect water samples, 

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send them to the lab for microbiological analysis, 

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and review and document the results that the lab passes along.


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