All around the world, people rely on water filtration. From industrial wastewater processing to the filter you use for the tap water coming out of your kitchen sink, clean water matters every day. But how clean is the water you’re using to do your laundry? Recently, a client approached Particle Technology Labs (PTL) to help them answer this very question.
The Question
Laundry Services Company (LSC) provides laundry equipment, maintenance, and consulting services to laundromats, hotels, and other commercial laundry operations. On top of this, they also run several of their own laundromat locations. When LSC was planning to purchase a new laundromat location, they wanted to see if the site’s water treatment system was filtering out contamination.
But LSC ran into a problem: the site’s treatment should be working, and they believed that it was, but they had no way to show it. Without specialized analytical equipment, small particle contamination is often invisible to the naked eye, and you can’t be sure of what you can’t measure.
That’s where PTL comes in.
So, what exactly did LSC need to know, and how can PTL show that the water treatment is doing the job? The answer lies in one of the most commonly used analytical techniques we have in our arsenal.
But before we get into how, let’s talk about why.
Why it Matters
Clean water is important for so many reasons. We all know this, but how often have you thought about particulate that might be in the water washing your clothing?
Of course, the cleaner the water, the better the wash quality and the happier the customer, but a high concentration of particulate in the water could also lead to unnecessary wear and tear on LSC’s equipment. And, for LSC, this was an important consideration when investing in a new laundromat.
PTL was here to help give LSC and their customers peace of mind.
The Analytical Approach
To answer LSC’s question, PTL recommended Single Particle Optical Sensing (SPOS), which uses light obscuration for particles larger than 1.5 µm and light scattering for particles smaller than 1.5 µm. This particle counter technique is commonly used for water samples when contamination concentration is in question, and it is widely accepted by numerous international standards and guidance agencies such as ISO, USP, and ASTM.
SPOS’s ability to detect small percentages of outliers, measure overall particle size distribution, and provide particle concentration data made it the easy choice for LSC’s testing needs.
To isolate the effect of LSC’s water treatment, they sent PTL two samples:
- Control sample: untreated city water
- Test sample: the city water after it had gone through the water treatment system
PTL measured both samples in the same way, generating data for both volume- and number-weighted particle size distributions. More importantly, we generated particle concentration data for each sample. If the particle concentration was lower in the test sample than in the control sample, this would indicate that the water treatment was working to reduce particulate contamination.
The Payoff
So, what did the numbers say?
The data tells a clear story. The control sample (untreated city water) contained approximately 1.87 x 105 particles per milliliter at .50 µm and larger. After passing through the laundromat location’s treatment system, that concentration dropped to roughly 1.08 x 104 particles/mL, over 17 times fewer particles in the treated water than in the untreated control.
So, we were able to tell LSC that, yes, the treatment was working, and the SPOS data gave them something they didn’t have before: objective, third-party confirmation that their system is doing exactly what it is designed to do.
For LSC, this kind of independent, quantitative data does more than settle an internal question. It gives them evidence that they can stand behind when discussing water quality with customers, added confidence in their treatment systems, and, most importantly, it gave them valuable insight toward their purchasing decision. What was once an assumption is now a documented result.
The Bigger Picture
LSC’s question is a version of one that comes up across many industries: is this treatment step actually doing what it’s supposed to do? The same before-and-after SPOS approach used here can apply just as well to municipal and industrial water treatment, process and wastewater studies, and even emerging applications like data center cooling systems, where liquid cleanliness plays a direct role in equipment reliability and performance.
Wherever there’s a treatment, filtration, or cleaning process that needs to be tested, particle counting can turn an uncertainty into measurable results.
Conclusion
LSC came to PTL with a straightforward but important business question: was the water treatment at a new location they were considering noticeably reducing particulate contamination? Without the right analytical tools, that question would have stayed unanswered.
Using Single Particle Optical Sensing, PTL was able to turn “we think it’s working” into “we can show that it does work.” That’s the value of pairing the right analytical technique with the right lab, turning the murky waters of the unknown into a result you can point to.
Have a tough particulate question you can’t answer on your own? Don’t worry. PTL has your back. Send us a message, and let’s get to the bottom of things together.
By Zach McNeil, Technical Communications Lead
