A Story From the Field: A Pool That Used to Be Full of Laughter

Kru Nan has run a children's swim school in Sam Khok district for several years. A mid-sized pool sits in the middle of an airy, roofed building, with benches around the edge where parents wait and watch. Along one side are the boys' and girls' shower rooms, a locker room lined with metal lockers, and an equipment store packed with kickboards, swim rings, pool noodles, fins, goggles and foam mats for the youngest learners. At the front are a reception counter, a small office and a carpeted waiting corner for parents.

This year the Chao Phraya rose so high that water spilled into the village. The flood covered the pool deck, shower rooms, locker room and equipment store to about mid-shin. Murky floodwater poured into the pool, turning it brown, and it stayed that way for days. Kru Nan had to cancel every class through the parents' LINE group.

When the water finally receded, Kru Nan opened the equipment store and had to step back from the damp, stale smell. The bright kickboards had black spots growing along the cracks in their foam. The pool noodles leaning against the wall were coated with something slippery. The toddlers' foam mats were caked in mud. In the shower rooms, the tile grout had turned black and the drains gave off a foul smell. The metal lockers were starting to rust, and the carpet in the parents' corner was soaked and musty.

A few days later, the messages from parents began. "When will lessons start again? My son keeps asking." Others were more direct: "Are the pool and the showers safe now?" Kru Nan knew that for a school that looks after small children, the answer had to be clear and backed by real steps.

If you run a swim school, a village or condominium pool, a fitness centre with a pool, or a sports club in Sam Khok or nearby, and you are facing the same situation after the 2026 floods, this article will help you plan the order of work.

Why Swim School Facilities Grow Mold So Quickly

• They are humid even on a normal day. Shower rooms and pool halls already run at high humidity. After a flood, that baseline moisture combines with soaked walls and floors, so nothing has a chance to dry.
• Foam equipment is porous. Kickboards, noodles and mats are made of closed-cell foam, but once the outer skin cracks, water and dirt get inside and mold follows.
• Grout and sealant absorb water. The joints between tiles are far more porous than the tiles themselves and hold floodwater and organic matter for a long time.
• Lockers and benches create hidden corners. The gaps behind and beneath metal lockers and fixed benches rarely get cleaned or aired, so mold can grow out of sight.
• Ceilings collect condensation. Warm, wet air rises and condenses on shower room ceilings and in ceiling voids, which is why black spots often appear overhead first.

Why a Swim School Needs Extra Care After a Flood

Young children are a higher-risk group

Children often swallow water during lessons, like to sit and play on shower room floors, and touch their faces constantly. Floodwater that has run across roads and through drains is usually contaminated with sewage-related germs such as E. coli, which can cause diarrhea. Wet, warm floors are breeding grounds for fungi that cause skin conditions such as athlete's foot, and children with allergies or asthma may react to mold spores in damp rooms. Adults wading through water during the clean-up also face a risk of leptospirosis if they do not wear boots. The World Health Organization and Thailand's Department of Health both stress hygiene and safe clean-up after floods.

The pool water is no longer clean water

Once floodwater has entered the pool, it contains mud, leaves, germs and other contaminants. Simply adding more chlorine is not enough. A qualified pool technician or pool service company needs to assess the pool, drain it, clean it, check the filtration system and test the water quality before it is used again.

Pool chemicals can be dangerous

If the chemical store that holds chlorine and water-balancing products was flooded, containers may be leaking or products may have become wet. Some of these chemicals release dangerous gases when they mix. Never combine them or wash them down a drain yourself. Let a chemical handling specialist or your pool service company deal with them.

Parents' trust

Parents choose a swim school because they trust it with their children. If a child falls ill soon after lessons resume, or a parent notices a musty smell in the shower room, trust that took years to build can disappear very quickly.

Why Scrubbing the Showers and Reopening Is Not Enough

• Scrubbing floors with bleach alone. It helps with stains on the tile surface but does not reach mold in the grout, under benches, behind lockers or in damp ceiling panels.
• Mixing several bathroom cleaners together. Bleach combined with acidic or ammonia-based cleaners can release dangerous gases, especially in poorly ventilated shower rooms.
• Washing foam training equipment and using it straight away. Once foam is cracked or its skin has peeled, mold grows into the foam itself. Surface washing does not remove it, and black spots will return.
• Lighting scented candles or spraying fragrance in the waiting corner. This only masks the smell. A carpet that was soaked in floodwater is still a source of germs and odor.
• Running fans in the equipment store. Fans help things dry faster but also spread mold spores throughout the room.

The principle is to let pool specialists take care of the water, and treat the dry-side rooms as a separate job. Pool water, filtration and water testing belong to pool professionals. Shower rooms, lockers, equipment stores and waiting areas are where WHD helps directly.

The Recovery Order for a Swim School (Before and While Our Team Works)

1. Electrical system and pumps. Have a qualified electrician inspect the wiring, pool pumps and shower water heaters before anything is switched on.
2. Pool and filtration. Have a pool technician or pool service company drain the pool, clean the floor and walls, clean or replace the filter media, and test the water until it meets safe standards.
3. Pool chemical store. Have specialists inspect and deal with any damaged containers. Never mix or dispose of chemicals yourself.
4. Remove mud and wash floors. Wash the pool deck, shower rooms and locker room with clean water and detergent, always wearing gloves and boots.
5. Sort the equipment. Kickboards, noodles and foam mats that are cracked, peeling or have deep mold should be thrown away and replaced. Hard plastic items such as rigid rings, baskets and training cones can be washed.
6. Carpets and towels. Waiting-area carpet and towels that sat in floodwater should usually be discarded or sent for specialist laundering.
7. Lockers. Open every locker to let it dry, wipe off rust and mud, and remove any items customers left behind.

Please note: WHD does not treat pool water, test water quality or handle pool chemicals. Those tasks must be carried out by a pool technician or pool service company. Our job is to disinfect flood-borne germs, reduce mold and remove musty odors in the shower rooms, locker room, equipment store, parents' waiting area and office.

The Solution: Disinfection Fogging for Wet Areas, Ozone Treatment for Rooms That Can Be Closed

WHD's disinfection fogging service uses CHEMGENE HLD4H applied through a ULV fogger that produces a fine mist. It reaches shower room floors, grout lines, the undersides of benches, the backs of lockers, the pool deck and parents' benches, helping to deal with flood-borne germs and surface mold. Our team does not spray into the pool water itself, which is a job for pool specialists.

Our ozone treatment service suits rooms that can be closed, such as the shower rooms, locker room, equipment store, office and an enclosed waiting area. Ozone helps destroy airborne mold spores and break down odor molecules trapped in ceilings, walls and drains. Before treatment, our team checks that chlorine and other pool chemicals have been moved out of any room being treated.

Much swim training equipment is made of foam and rubber, including fins, goggle straps and swim caps, which can deteriorate faster under high ozone concentrations. We therefore recommend moving equipment you intend to keep out of the room before treatment. We use a controlled concentration and duration, and cover or remove electronics such as the reception computer and hair dryers first.

Ozone safety: during treatment there must be no people, children, pets or plants in the space. Afterwards, doors and windows are opened to ventilate until the ozone has broken down, before teachers and students return.

How the WHD Team Works in a Swim School

1. Site survey. We check the water line and mold in the shower rooms, locker room and equipment store, and locate the pool chemical store.
2. Coordination with your pool technician. We plan the sequence so that pool cleaning and our fogging work do not clash.
3. Preparing the space. Foam and rubber equipment you are keeping is moved out, pool chemicals are removed from rooms being treated, and electrical equipment is covered.
4. Disinfection fogging. CHEMGENE HLD4H is applied in the shower rooms, locker room, pool deck, waiting area and equipment store.
5. Ozone treatment. The shower rooms, locker room, equipment store and office are sealed, machines are set according to room size, and the duration is controlled.
6. Ventilation. Doors, windows and extractor fans are opened until the air is safe.
7. Re-check. We check odor and mold again and advise on keeping shower rooms dry at the end of each teaching day.

Daily Habits That Keep Shower and Locker Rooms Fresh

Swim schools are wet places every single day, flood or no flood. Once the rooms have been restored, these routines help stop mold and odors from returning:

• Squeegee and dry the floors after the last class of the day instead of leaving standing water overnight.
• Run extractor fans for at least an hour after closing, and check that they actually pull air out of the room.
• Prop locker doors open overnight once a week so the insides can dry.
• Store equipment on open racks where air can circulate, rather than piling kickboards and noodles in bins.
• Rinse and dry foam equipment after use, and retire any piece that cracks or peels.
• Wipe high-touch surfaces such as benches, handrails, door handles and shower taps with a suitable disinfectant such as CHEMGENE HLD4H spray, applied to a cloth.
• Keep drain traps filled with water so sewer gases cannot rise into the shower rooms, and call a plumber if drains still smell.

A Sample Reopening Timeline

Every site is different, and the real timeline depends on how deep the water was, how long it stayed and how quickly your pool technician can work. As a rough guide, many small swim schools find it helpful to think in stages rather than a single reopening date:

• Stage one: make it safe. Electrical inspection, removal of mud, and safe handling of the pool chemical store. No lessons, and no children on site.
• Stage two: restore the pool. Your pool technician drains, cleans and refills the pool, services the filtration system and tests the water. At the same time, damaged equipment, carpets and towels are cleared out.
• Stage three: restore the rooms. WHD fogs and ozone-treats the shower rooms, locker room, equipment store and waiting area once they are clean and the chemicals have been moved.
• Stage four: soft reopening. Start with a smaller timetable or older groups, check how the rooms smell and dry at the end of each day, and gather feedback from teachers.
• Stage five: full timetable. Once everything is stable, return to your normal schedule, including the youngest learners.

Moving through these stages in order gives you a clear story to tell parents and reduces the chance of having to close again because of a problem that was missed.

How to Talk to Parents About Reopening

Parents do not need technical detail, but they do want to know that you have taken the right steps in the right order. A short, honest update builds far more confidence than a simple "we're open again".

• Explain the sequence. Tell parents that the pool was drained and cleaned by a pool service company and the water was tested, and that the shower rooms, locker room and equipment store were disinfected and ozone-treated.
• Mention the new equipment. Let them know that damaged foam kickboards, noodles and mats were replaced rather than reused.
• Share a few photos. Clean shower rooms, tidy equipment racks and a clear pool say a lot in a LINE message.
• Invite questions. Offer a time when parents can visit before the first lesson and see the facilities for themselves.
• Ask parents to help. Encourage them to keep children home if they are unwell and to remind children not to swallow pool water.

Protecting Teachers and Staff During the Clean-Up

Swim teachers often pitch in to help clear the building, but they are also the people who will be in the water with children every day once lessons restart. Look after them during the recovery:

• Provide boots, rubber gloves and masks, and make sure they are worn whenever anyone handles mud, wet foam or soaked carpet.
• Cover cuts and grazes with waterproof dressings, and wash thoroughly with soap and clean water after contact with floodwater.
• Keep staff out of the pool until your pool technician confirms the water has been cleaned and tested.
• Ask anyone who develops a fever, muscle aches, diarrhea or a spreading rash after the flood to see a doctor and mention their exposure to floodwater.
• Keep at least one clean toilet and handwashing point available on site throughout the work.

10 Reasons Swim Schools in Sam Khok Choose WHD

1. We use disinfection fogging that reaches grout lines, under benches and behind lockers.
2. We use ozone treatment to reduce musty odors in shower rooms and equipment stores.
3. We use CHEMGENE HLD4H for high-level disinfection.
4. We coordinate with your pool technician so the work does not overlap.
5. We always check that pool chemicals have been removed before ozone treatment.
6. We control ozone concentration and advise on moving foam and rubber equipment.
7. We pay attention to surfaces children touch most, such as benches, handrails and shower floors.
8. We help you explain your recovery steps to parents clearly.
9. We follow clear safety steps, with no people or pets in the area during ozone treatment.
10. We offer related services such as dust mite removal for sofas and cushions in the parents' waiting corner.

Before and After: A Swim School Recovery

Customer Voice (Example Scenario)

"I was planning to top up the chlorine and scrub the showers in a day. The team suggested calling a pool technician to deal with the water first, then fogging and ozone-treating the showers and equipment room in the right order. Having a clear sequence made it easy to explain to parents. All the children came back, and nobody has complained about smells in the shower rooms."

— Kru Nan, swim school owner, Sam Khok (an illustrative scenario based on typical site situations)

Frequently Asked Questions

Q: Can WHD disinfect the pool water too?
A: No. Pool water, filtration and water testing must be handled by a pool technician or pool service company. WHD takes care of the pool deck, shower rooms, locker room and equipment store.

Q: Can foam training equipment be ozone-treated and reused?
A: Foam that is cracked or has deep mold should be replaced. Foam in good condition should be washed, dried and moved out of the room during treatment, because high ozone concentrations can make foam and rubber deteriorate faster.

Q: Our shower room smells like drains. Will ozone help?
A: Ozone helps reduce musty odors in the room, but if the smell comes from a blocked drain or a dried-out trap, a plumber should fix that first.

Q: Can teachers stay in the building during ozone treatment?
A: Not in the rooms being treated. There must be no people, children, pets or plants there, and the rooms must be ventilated until safe before anyone returns.

Q: How should we tell parents what we have done?
A: Share the steps honestly: the pool was cleaned and tested by a pool service company, the shower rooms and equipment store were disinfected and ozone-treated, and damaged equipment was replaced.

Q: Should we replace the shower room ceiling panels?
A: If ceiling panels are sagging, stained right through or crumbling, they usually need replacing, and a builder should check the space above them. Panels that are sound but show surface spots can be cleaned and then treated along with the room.

Q: Do you serve areas outside Sam Khok?
A: Yes. We work across Pathum Thani, Bangkok, Ayutthaya and nearby provinces. Contact us to check scheduling for your location.

Ready to Welcome the Children Back to the Pool

Talk to the WHD team about disinfection fogging and ozone treatment for your shower rooms, locker room, equipment store and parents' waiting area in Sam Khok and nearby areas.

See Disinfection Service — Click Here

Book Ozone Treatment — Click Here

Call 065-556-6294 · LINE @whd268 · Email worldhealthdisinfection@gmail.com

Related Links

• Residential ozone disinfection
• Ozone treatment for odors and chemical residue
• CHEMGENE HLD4H disinfectant spray
• All articles

Health reference: World Health Organization (WHO): Floods · Department of Health, Thailand