Immersion and rinse test (Swoosh Test) for its washable diapers
Coralie Mabouledecouche
The Swoosh Test is the gold standard for checking if your cloth diapers are soiled. Simple, quick, and revealing, it helps you adjust your detergent dosage to achieve optimal absorbency. Here's how to perform the test, interpret the results, and avoid the most common mistakes.
Summary
What is the Swoosh Test?
The Swoosh Test determines if your cloth diapers are soiled or poorly rinsed . Contrary to popular belief, soiling is not always caused by too much detergent: a lack of detergent can also leave urine and limescale residues in the fibers.
These residues prevent water from penetrating properly, decrease absorption and can irritate baby's skin.
Why test for soiling of washable nappies?
A balanced wash ensures optimal diaper performance. Buildup, whether due to too much or too little detergent, often leads to:
- Recurring leaks ;
- Bad smells ;
- Skin irritations ;
- Ineffective washing despite a visually clean appearance.
👉 This test complements good machine maintenance and a dosage adapted to the hardness of your water .
How to perform a Swoosh Test
Materials : a clean insert, a container and very hot water.
- Fill the container with hot (not boiling) water;
- Immerse the clean insert and wait a few minutes;
- Shake gently ("swoosh");
- Wring out in the container;
- Observe the water: colour, bubbles, foam.
💡 Ideally, try a bamboo or hemp insert for a more revealing result.
How should the results be interpreted?
- Clear water without foam: clean diapers but perhaps not washed enough;
- Slight foam: residual presence of detergent, rinse required;
- Excessive foam: layers saturated with detergent; repeat several rinses with clean water.
How to correct an excess or lack of laundry detergent?
Too much laundry detergent?
- Perform several rinses with clean water ;
- Run a cycle without detergent at 40°C;
- Add a little baking soda to dissolve the residue.
Not enough laundry detergent?
- Wash at 60°C with the full dose;
- Use a suitable laundry detergent without glycerin ;
- Finish with a long rinse to remove any remaining detergent.
How to prevent clogging?
- Use a detergent suitable for natural fibers (bamboo, hemp, modal);
- Adjust the dosage according to the hardness of your water ;
- Fill the machine to ⅔ for optimal mechanical action;
- Perform a monthly Swoosh Test to anticipate clogging.
FAQ – The Swoosh Test
How often should a Swoosh Test be performed?
Once a month is sufficient to check the internal cleanliness of the fibers and adjust the detergent dosage before the diapers lose absorbency.
What water temperature should I use?
Hot but not boiling water: between 60°C and 70°C so as not to damage the natural fibers.
Does the test work on all types of inserts?
Yes, but it is more revealing on bamboo or hemp inserts, because they retain more residue.
Can the Swoosh Test be performed on a full layer?
No, only on the absorbent insert. The PUL panty is not tested in this way.
Does the Swoosh Test replace a cleaning process?
No. It is used for diagnosis; if it reveals an excess of residue, machine cleaning is necessary.
Conclusion
The Swoosh Test is a simple and precise way to maintain the effectiveness of reusable nappies. It helps find the perfect balance between washing and rinsing, guaranteeing baby comfort, hygiene, and lasting softness.
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