The Pool Water Was Perfect - the Changing Room Was Not. How a Public Pool Stopped Fungal Infections With the Airofog U260
Last updated: 2 Sep 2026 | 59 Views |
The Pool Water Was Perfect - the Changing Room Was Not. How a Public Pool Stopped Fungal Infections With the Airofog U260
Every pool spends money and effort on water quality, and rightly so. But people are not in the water the whole time. They walk barefoot across permanently damp floors, for dozens of metres, twice - on the way in and on the way out.
What actually happened — Three dermatology receipts in one week
Kittipong manages the 25-metre pool at a suburban sports centre, serving an average of 280 users a day: children's swimming courses, a morning seniors' club and office workers who swim in the evening.
He was proud of his water quality. Chlorine and pH tested three times daily and logged every time, filtration running 24 hours, and not a single water-related complaint in the six years he had worked there.
Then, one week in August, he received three complaints in five days.
The first came from the mother of a nine-year-old in the children's swimming course, with an itchy rash and peeling skin between the toes on both feet. The doctor diagnosed athlete's foot.
The second came from a member of the morning seniors' club with a hard, painful lesion on the sole of his foot. The doctor diagnosed a plantar wart, caused by a virus transmitted on wet floors.
The third came from an office worker who swam in the evenings, with a fungal infection in the groin, and who stopped swimming for over a month.
Kittipong says his first reaction was to go and retest the chlorine immediately. Everything was normal. He sent water samples to a laboratory. They passed every parameter.
He sat with it for a long time. If it is not the water, what is it?
The answer came from the centre's nurse, who said in a meeting: walk the route the children walk. From the door to the poolside.
So he did. He took off his shoes at the door as the rules require, and walked barefoot along an 18-metre corridor, through a changing room with wooden benches and tiled floors, past eight shower cubicles with water standing on the floor all day, past the footbath, and out to the poolside.
For that entire route his bare feet touched wet floor at every step - the same floor 280 people a day walk across.
When he asked the cleaning team how those floors were maintained, the answer was: mopped with detergent twice a day, morning and evening. That sounded reasonable, until he asked how many people walked through between those two passes. The answer was about 150.
Worse, the wooden benches in the changing room - where people sit bare-skinned after showering - the drain grates that had never been lifted for cleaning, the shower walls with black staining along the grout, and the permanently damp locker interiors, appeared on no cleaning schedule at all.
Kittipong summarised it to management that day: we invest fully in the pool water, and we have let the walkway to the pool go essentially unmanaged for six years.
The damage nobody puts on the invoice
A public pool's real problem is not in the water. It is in the space around the water, which is far more favourable to pathogens than most people assume.
1. Permanently wet floors and bare feet
Almost every pool requires shoes to be removed before entering the wet area, which is correct for water quality - but it means every user walks barefoot across shared public flooring for dozens of metres.
Athlete's foot and plantar warts are both transmitted directly on shared wet flooring walked barefoot. Thailand's Department of Disease Control identifies shared wet areas - pools, communal showers and changing rooms - as the primary risk settings for this group of conditions.
Humidity that never clears means these organisms survive on the floor far longer than they would in a dry environment.
2. The gap between cleaning passes
Mopping twice a day sounds reasonable on paper. But if 150 people walk through between the two passes, then the floor the 150th person steps on has accumulated whatever the previous 149 left behind.
And mopping has a limitation people overlook: it also redistributes material from one place to another, especially when the mop head is not rinsed between zones.
The places a mop cannot reach at all - under benches, inside drain channels, along tile grout, in shower corners - continue to accumulate regardless.
3. Two unusually vulnerable user groups
Public pools have two user groups at considerably higher risk than the general population: young children in swimming courses, and older adults in exercise clubs.
Children have thinner skin and rarely dry their feet properly. Many older adults have underlying conditions such as diabetes, which slows healing of foot lesions and raises the risk of a small problem becoming a serious one.
For an older adult with diabetes, a small foot lesion is not a small matter - and that is a responsibility pool operators need to recognise.
4. Word of mouth that destroys memberships
Pool businesses live on annual memberships and children's swimming courses, and both are driven overwhelmingly by word of mouth among parents.
When one parent mentions in a class group chat that their child caught a fungal infection at the pool, the effect does not stay within one family. It spreads across the whole group.
Kittipong says 14 parents did not renew their children's courses the month after the incident - an unusually high number - and he suspects there were more who simply did not give a reason.
Why the usual fixes keep failing
Kittipong tried the things pools usually try, and found each had its own ceiling.
- Increasing mopping to four times a day helped somewhat, but left the floor wet more often, raising slip risk - and there was still a gap between passes with dozens of people walking through.
- The footbath before entering the pool is useful for reducing what enters the water, but the bath itself is standing water that everyone steps into. Unless the water is changed frequently it becomes a transmission point rather than a barrier.
- Asking users to bring their own sandals is good advice but unenforceable in a public facility, and a great many people forget them.
- Scrubbing grout and deep-cleaning showers monthly is necessary for removing accumulated staining, but during the month in between, organisms have time to re-establish on permanently damp surfaces.
- Hand dryers and fans help comfort but do not meaningfully dry the floor, because the moisture source is people walking out of the pool wet, all day long.
- Wiping benches and lockers almost never happens, because there are many of them and users' belongings are on them throughout opening hours.
What the professionals reach for — Airofog U260
What Kittipong needed was a method that treats every surface at once, in a short window after closing, achievable every day without extra staff.
ULV - Ultra Low Volume - fogging answers that directly. It releases an enormous number of micron-scale disinfectant droplets that travel throughout the room, down into drain channels, along tile grout, under benches, into lockers left open and across shower walls, settling on surfaces from every direction in a single pass.
The Airofog U260 is a German-built ULV fogger producing 15-30 micron droplets, particularly well suited to a wet facility because it does not add water to floors that are already wet. It uses a very small liquid volume to lay down a thin film, unlike hose washing which leaves the floor wetter than before.
It also fits how a pool operates. Pools already have a defined closing period. Treating both changing rooms, the showers and the poolside walkway takes roughly 15 to 20 minutes in total, which slots neatly into the nightly close-down.
10 reasons the Airofog U260 actually solves this
1It reaches drain channels nobody ever lifts
Drain grates and the channels around the pool are the wettest and dirtiest places in the building, and are almost never lifted for cleaning because it is heavy and slow. The U260's 50 cm gooseneck hose lets an operator fog directly into the channel without lifting the grate.
2It penetrates tile grout and shower corners
Black staining in grout is a sign of established fungal growth, and shower corners are where a mop genuinely cannot reach. Micron droplets disperse into those crevices and corners thoroughly in a single pass.
3It does not add water to an already wet area
This is the single biggest advantage in a pool context. ULV uses only millilitres per minute; the droplets lay down a thin film and dry, adding no pooling and no additional slip risk - unlike hose washing.
4It covers benches and lockers that are never wiped
The wooden benches people sit on bare-skinned after showering, and the permanently damp locker interiors, are the two highest-risk and most neglected surfaces. With lockers left open, one pass coats their interiors and the benches together.
5Every night, in 15 to 20 minutes
Frequency decides the outcome in a permanently humid space. Treating both changing rooms, the showers and the poolside walkway takes under half an hour for one person - genuinely achievable nightly after closing.
6It works outdoors around the pool deck too
Many pools have an outdoor deck with sun loungers, handrails and pool ladders - all shared contact points. The U260's output covers these areas in the same round.
7Six nozzle settings to match the surface
Tiled floors and drain channels tolerate a heavier application, while wooden benches and areas near electrical fittings such as hand dryers need a lighter one. Six settings mean one machine serves every zone.
83.4 kg lets one person cover the whole building
Most pools run only one or two night cleaning staff. A light machine means one person can walk both changing rooms, the showers and the poolside walkway without stopping.
9Documentation you can show parents and local health officers
When a parent asks what measures are in place, or the local health authority inspects, the Airofog U260 carries certification from Thailand's Department of Medical Sciences, Department of Health and the Faculty of Medicine at Mahidol University, plus WHO, TUV Rheinland and IPARC.
10It becomes a selling point for children's swimming courses
Parents choosing a swimming course care about two things: water safety and hygiene. Nightly changing room disinfection with a log to show is something most local competitors still do not have.
Before vs after the Airofog U260
Kittipong says he never expected the last row. He simply wanted the complaints to stop. But being able to tell parents exactly what happens every night turned out to be the reason new parents chose the centre.
A practical 7-step rollout plan
Pools that make this work build the pass into the nightly close-down checklist, so it becomes part of closing rather than an optional extra.
Step 1: Map the barefoot route your users actually walk
Walk the real route from the shoe-removal point to the poolside and mark every place a bare foot touches the floor. That route is your complete treatment list.
Step 2: Tie the pass to the close-down procedure
Run it after the last user leaves and after the evening mop, and make it a signed line item on the nightly close-down checklist.
Step 3: Leave unrented lockers open every night
Make it policy that lockers without a monthly renter stay open after closing, so droplets reach the interior and the locker dries overnight.
Step 4: Lift benches and grates twice a week
At least twice weekly, lift the drain grates and tip the benches on edge before fogging, so droplets reach the floor beneath - where accumulation is heaviest.
Step 5: Empty and treat the footbath nightly
The footbath is stepped in by everyone. Drain it, scrub it, and fog the basin before refilling the next morning.
Step 6: Log it and show your users
Record date, time, zone, chemical and operator, and post a weekly summary on the noticeboard so parents and members can see what actually happens.
Step 7: Review quarterly with your health staff
Review skin and foot complaint numbers each quarter with the centre's nurse or health officer to confirm the measure is still working and identify anything to adjust.
Airofog U260 full specification
For a pool, the two decisive specifications are the 50-200 ml per minute output, low enough not to add standing water to an already wet floor, and the 50 cm gooseneck hose that reaches into drain channels.
From a real user
“For six years I tested chlorine three times a day without fail. Then one day I understood that I was looking after the water beautifully while leaving the eighteen-metre barefoot walkway essentially unmanaged.”
“My biggest worry was slip risk, because our floors are already wet. But ULV uses so little liquid that the floor is no wetter after a pass. That is the point at which my team agreed to do it.”
“Six months on there have been no further fungal or wart complaints. And what I had not anticipated is that when new parents ask about hygiene, I can show them a night-by-night log going back months. They are more impressed by that than I expected.”
— Pool manager, suburban sports centre (name withheld)
You already look after the water. It is time to look after the walkway everyone crosses barefoot.
See the Airofog U260 price and details - click here
Free consultation: 065-556-6294 | LINE @whd268
The World Health Disinfection team is happy to advise you before you decide, at no cost, and can prepare a quotation and the documents your procurement process needs.
Frequently asked questions
Will fogging make the floor more slippery?
No - the opposite. ULV uses only millilitres per minute, and 15-30 micron droplets lay down a thin film that dries rather than pooling. Unlike hose washing, it does not leave the floor wetter or require a long drying period.
How long do both changing rooms and the showers take?
In practice, both changing rooms, the showers and the poolside walkway take roughly 15 to 20 minutes for one member of staff - which fits into the nightly close-down.
Will the disinfectant affect the pool water chemistry?
In practice you treat only the surrounding areas, changing rooms and showers, avoiding fogging directly at the water surface. ULV liquid volumes are very small, and with the recommended standoff from the pool edge there is no effect on water balance.
Is nightly treatment really necessary?
In a permanently humid area used by hundreds of people daily, frequency is the decisive factor. Most pools start nightly in the changing rooms and showers, then add the poolside once they see how little time it takes.
Can it be used at an outdoor pool?
Yes, though choose a calm period so droplets settle properly - usually after evening closing - concentrating on sun loungers, handrails, pool ladders and walkway surfaces, which are the shared contact points.
Is it worthwhile for a small condominium or hotel pool?
Yes. A smaller area means a much shorter pass, and condominium and hotel pools rarely have specialist cleaning teams, so a machine one staff member can run in ten minutes is exactly the right fit.
Read next / related links
Read next / related links
- All ULV disinfection foggers
- Chemgene HLD4H disinfectant
- Professional disinfection service
- Certificates and test reports
Authoritative references
Related search terms: swimming pool disinfection, changing room hygiene, ULV fogger, Airofog U260, athlete's foot prevention, plantar wart prevention, communal shower disinfection, cold fogging machine
See full details and pricing for the Airofog U260 ULV fogger from Germany - click here
