What Does A Blue Line On Diaper Products Mean?

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If you have decided to use disposable diapers instead of reusable ones, you are in for a long cycle of buying products, changing endless diapers, and watching them soiled pretty quickly. One thing that you will notice with a lot of products, especially many of the Pampers ones, is that there is a little line running down them.

This isn’t a decorative feature. Instead, this is a highly practical tool called a wetness indicator. So, let’s learn more about the blue line on diaper products, why they are so helpful, and other important factors new parents need to know.


What Are Blue Lines On Pampers For?

If you have obtained a lot of Pampers diapers as a new parent – perhaps in bulk from family and friends – you may see that there is something called a wetness indicator within the diaper. At first, this is a little yellow strip at the front of the diaper that seems pretty inconsequential when putting the diaper on your child. But, it won’t be long until you look at your child and see that the line is now blue. This means that the diaper has been soiled and it is time to change it for a fresh one.


How Does A Wetness Indicator Work?

The basic idea here is pretty straightforward. There is a strip within the diaper that contains a helpful core of chemicals and other materials. Unlike the cores in our own sanitary products that hide the presence of moisture and allow for greater absorbency, this one is meant to stand out like a beacon when the diaper is wet.

The strip is usually yellow, to begin with when the diaper is fresh and dry, but then changes to a more striking blue. This means that we can see when our child has urinated in their diaper and get to them before it becomes a problem. There was a time when fade when wet technology was more popular, but this strip is now the go-to piece of tech for companies like Pampers.


What Makes The Diaper Strip Turn Blue?

These clever color-changing properties are the result of special agents within the strip. These chemicals react with the liquid as it seeps into the core for a fast reaction. These chemicals include the main reactionary liquid, but also some gels that help stop the diapers from being a fire risk, and some floral ones for a better scent. You also tend to find absorbers in there to help prevent leaks.


How Do I Know When To Consider A Diaper Wet?

Here is a video from Mary Cahill explaining how the wetness indicator on diapers works:


Are These Diapers With Wetness Strips Safe To Use?

You may worry here that these diapers aren’t the best choice for kids because of the chemicals needed for these reactions. This is not the most environmentally-friendly approach for using diapers for kids, but it is safe. There is little chance of a bad reaction and the agents used can help reduce the risks of rashes and other problems.

Why Blue?

Blue is a great color choice for this sort of product. On a basic chemical level, the substances within the strip include Bromophenol Blue to create a strong reaction to the presence of any liquid in the diaper. This bright blue – or more blue-green tone in some Pampers diapers – is something that you aren’t going to miss when it does appear on the white background of the diaper.

There is also the fact that we associate the color blue with water. It is unclear if this psychological factor was a consideration when creating the wetness indicator, but it makes the most sense. Yellow looks dry and blue looks wet. So, as soon as we see blue, we know it is time to change the diapers.

Huggies Brought Wetness Indicators Into Diapers In The Early 2000s.

You may associate Pampers with wetness indicators because of their blue strip. However, the concept of a visual alert came a little earlier in the Huggies Pull-Up training pant. These pants were part of a new line designed to help kids and parents handle leaks with greater ease. The first of these was arguably not as effective as the blue strip today.

The idea was that the ink used for the graphics on the diapers would fade when wet. This concept is still in use and has its benefits if you want something a little more aesthetically pleasing. But, the advancement of the blue strip is a clearer indication for parents because of the more dramatic color change.

Pampers Has One Of The Broadest And Most Popular Ranges Of Diapers With Wetness Indicators.

Pampers took over the technology and idea providing an indicator. Over time, this evolved to the blue strip we see today. The feature is now a big part of their range and we see it in various diapers and training pants. This level of consistency is great because it means that we can see the same effect throughout the early years of our children’s development. We can get used to it early on with basic diapers and then continue the process with the training pants.

The other reason that so many parents recommend the Pampers wetness indicator diapers is that there are other benefits to the products. There is a hypoallergenic layer to the material that helps to wick away moisture and protect kids between urination and changing time. Other advantages here are the fit of the diapers, which tend to have a great elasticated waist to prevent leaks and smell, and the ease of application through the tab methods.

They can be a little more than some other brands on the market, but you know you are getting a good product. OF course, if for any reason you are not comfortable using Pampers as a diaper brand, you can still use Huggies or look for alternative providers with their own version of the blue strip.

Wetness Strips Are Helpful, But Not 100% Effective

Generally speaking, you should be able to rely on a wetness indicator strip on any disposable diaper that has them. However, there are times when you will pick up your child and find they have filled their diaper and the strip isn’t blue. So, what’s going on here.

There is the possibility that the pee from their last urination didn’t soak the diaper in the right place to activate the strip, if it ends up too near the back then you might not know about it until it is too late. This isn’t uncommon with baby boys. It also shows why it is so important to fit the diaper correctly.

Another possible reason here is that the pee stream was too light to cause a strong reaction. Finally, there is the risk of indicators drying out in hot temperatures.

These potential issues highlight the need to check your child regularly and not rely solely on the strip. If the diaper feels heavy and damp when you pick up your child, but the strip is yellow, it could still be soiled. Also, don’t be afraid to trust your nose. A good diaper will mask the smell, but the odor is one of the best indicators of a soiled diaper.


Do Diaper Lines Turn Blue For Poop?

The main purpose of these wetness strips is to alert parents to the presence of urine in the diaper for rapid changes. But, we also need to change for solid waste too. That may not be deposited as close to the wetness strip and also may not have the water content needed to spark the desired reaction.

Still, there are times when the poop is wetter and will cause that response. In the end, it doesn’t really matter why the blue diaper strip appeared. What matters is changing it ASAP.


Why Are These Diaper Strips So Important?

You may read all this about the reactions and potential for failures and wonder why you should get one of these products. Why not just rely on other instincts and continue changing your child regularly. This is great for parents with the skills and experience to do this. But, there are lots of new parents that may miss cues or not realize how important it is to change a diaper as soon as possible.

Quick diaper changes reduce the amount of time that the baby’s skin is in contact with the waste matter. This means less time for a rash to arise or for any other health issue to emerge. It is also much more pleasant for kids to be in a clean diaper than one full of pee and/or poop. The wetness indicator blue strip can help parents respond faster as they continue to learn what to do.


Should You Use Brands With Blue Line On Diaper?

It is your choice whether or not to use these products with blue strips or not. It may be a good idea to give them a try and see if they improve your reaction times or not. If they do, your child may be more comfortable and rash-free. If they don’t, they may be a waste of money. Stick with what works best for you.



This post is written and edited by Sandy who is a clinical pharmacist with over 20 years of experience specializing in pre-natal and post-natal care.