A Story From the Field: Dr. May's First Morning Back

Along the Chao Phraya River road in Sam Khok district, Pathum Thani, a band of brown mud still clings to the edges of the sidewalks. The moment the water dropped low enough to wade through, Dr. May, a veterinarian who runs a small-animal clinic out of two shophouse units, unlocked her rolling shutter to see the damage for herself. There was no friendly barking to greet her the way there usually was. Instead, a wave of damp, sour air mixed with the unmistakable smell of drain water hit her as soon as the shutter rose.

On the walls of the exam room, a clear waterline ran at roughly knee height. Below it, small black and green spots of mold had already started to bloom. The coated steel recovery cages had mud packed around their wheels and hinges. A few pet beds that nobody had managed to lift out of reach were waterlogged, heavy and smelling faintly of vinegar and rot. In the bathing and grooming room at the back, the floor drain was clogged with silt and the tiles had a slippery film that no one wanted to walk on, let alone put a freshly shampooed poodle down on.

A few doors down, Tai's grooming salon was in the same condition. Her standing blow dryers had been under water. The stainless steel grooming tables were coated with fine sediment. Around the corner, Boss's small pet hotel, which looks after dogs and cats while their owners are at work or traveling, had to suspend boarding altogether. Three business owners on the same stretch of road, all asking the same two questions: "When can we reopen?" and "How can we be sure the place is clean enough for animals that may already have weak immune systems?"

Regular customers were already messaging on LINE to ask whether the shops were open. Some were very direct about their worries: they had heard that pets get sick after floods, and they were thinking specifically about leptospirosis and fungal skin infections. This is the real challenge facing pet businesses in Sam Khok and across Pathum Thani in 2026, now that the floodwater is finally receding.

Why Pet Businesses Face Higher Risk Than Ordinary Homes

A flood does not just bring water indoors. It carries whatever was in the drains, septic tanks, rice fields and riverbanks it passed through. When the water drains away, much of that contamination stays behind in the mud, in cracks and joints in the floor, and inside anything porous that soaked it up. For veterinary clinics, groomers and pet hotels, that leftover contamination matters more than it does in a typical house, for several reasons.

1. Health risks for animals and people

• Leptospirosis. This bacterial disease spreads through the urine of rats and other rodents, which ends up mixed into floodwater. Dogs and humans can both be infected, usually through cuts, scratches or mucous membranes. Animals that lick floors or walk through muddy residue are especially exposed, and so are staff who handle them.
• Gut infections. Sewage-contaminated water can carry bacteria such as E. coli and other organisms that cause diarrhea in pets and in the people who care for them.
• Mold and airborne spores. Mold growing on walls, ceilings and bedding releases spores into the air. Those spores can trigger allergies and breathing problems, and they hit sick, very young and senior animals hardest. A recovery ward full of post-surgical patients is exactly the wrong place for a spore-laden atmosphere.
• Skin problems. Constant humidity and fungi in the environment make itching, dermatitis and hair loss more likely in animals that come in for a bath or stay overnight.

2. Reputation and trust

Most pet owners treat their animals as family members. If a dog goes home from a groom and starts scratching, or a cat develops diarrhea after a weekend at a pet hotel, the owner's first instinct is usually to connect it with the last place the pet visited, even if the real cause was something else entirely. In a close-knit area like Sam Khok, where customers find businesses through neighbors, Facebook groups and LINE chats, a single negative post can undo years of loyalty. The reverse is also true: a business that explains clearly what it has done to make its premises safe after the flood, and shows it, often comes out of a crisis with stronger customer trust than before.

3. Money and time

Every day the doors stay shut is lost revenue, and fixed costs such as rent and staff wages keep running. The temptation is to reopen as fast as possible. But reopening before the space has been properly disinfected can mean closing again a few weeks later when mold returns or odors creep back, which costs more than doing it correctly the first time. A clear, well-sequenced recovery plan is cheaper over the long run.

The Usual Quick Fixes, and Why They Fall Short

When you are under pressure to reopen, it is natural to reach for whatever you can do right now. These steps help a little, but none of them solves the whole problem.

• Pouring bleach everywhere. Bleach can disinfect smooth, non-porous surfaces, but its harsh fumes irritate animals, whose noses are far more sensitive than ours. A clinic that reeks of chlorine makes anxious pets even more anxious. Bleach also cannot reach behind cages, under cabinets or into the gaps between tiles, and it does nothing for the musty smell trapped inside plaster, wood and fabric.
• Running fans to dry things out. Fans help surfaces dry, but they also stir up mold spores and spread them into rooms that were not affected before.
• Air fresheners and scented sprays. These only mask the odor for a few hours. The source is still there, and some fragrances irritate the airways of cats, dogs and especially small pets and birds.
• Painting over the stains. Fresh paint looks great on day one. But if the wall behind it is still damp and full of fungal growth, the mold will push through again within weeks, often with a worse smell.

The common weakness of all these methods is that they only treat what you can see. Germs, spores and odor molecules are spread through the air, hidden in crevices and soaked into materials. To deal with them properly, you need a method that reaches the whole volume of the room, not just the surfaces within arm's reach.

The Solution: Chemgene HLD4H Fogging Plus Ozone Treatment by World Health Disinfection

World Health Disinfection (WHD) restores flood-affected spaces with two complementary treatments: our disinfection fogging service and our ozone treatment service. One targets germs on surfaces; the other targets what remains in the air and inside materials.

Ultra-low-volume (ULV) disinfection fogging

Our team uses CHEMGENE HLD4H, a high-level disinfectant used in medical and veterinary settings, delivered through a fogger that produces a very fine mist. The droplets hang in the air and settle evenly on every exposed surface, reaching behind cages, under exam tables, behind medicine cabinets and into the corners of bathing rooms that a mop or cloth simply cannot reach. Because Chemgene has a mild odor rather than a sharp chemical smell, it suits spaces where animals with sensitive noses will soon be returning.

Ozone shock treatment

After fogging, the team seals the area and runs a high-output ozone generator such as the Master Ozone Generator. Ozone is a gas, so it penetrates every gap and cavity in the room. It helps destroy airborne mold spores and bacteria, and it breaks down the molecules responsible for musty smells, drain odors and the stale animal smell that builds up in porous materials. Once the treatment cycle ends and the space is ventilated, ozone naturally reverts to ordinary oxygen and leaves no chemical residue behind.

Our six-step service process

1. Site survey. We assess how high the water reached, where mold is visible, which rooms smell worst, and plan the order of work. In a clinic, for example, we usually prioritize the operating room, recovery ward, bathing area and boarding rooms.
2. Mud removal and clean-up guidance. We advise on shoveling out mud, washing floors, discarding soaked bedding and materials that cannot be saved, and moving electronics and medical supplies out of the way.
3. Chemgene fogging. We fog every room and every surface, including cages, tables, bathtubs and drains.
4. Ozone treatment. Doors and windows are closed, generators are positioned according to room size, and the space is treated for a duration matched to how severe the odor and mold are.
5. Ventilation. Doors and windows are opened and exhaust fans run until the ozone has fully dissipated, before any person or animal comes back in.
6. Re-check and advice. We inspect the space again for odor and visible problems, and give practical advice on day-to-day cleaning so mold does not return.

How to Prepare Before Our Team Arrives

Pet businesses have more moving parts than a private home. Good preparation makes the job faster and keeps every animal safe.

• Contact owners in advance. Pet hotels should ask owners to collect their animals before treatment day, or arrange temporary boarding elsewhere.
• Relocate patients who need ongoing care. Clinics should coordinate with a partner clinic or set up a separate area that is completely outside the ozone treatment zone.
• Secure food, medicines and vaccines. Move them out or seal them properly, and keep vaccine refrigerators in a room that is not being treated.
• Remove all aquariums, bird cages, small mammals and houseplants. Small animals and plants are very sensitive to ozone.
• Throw away materials that cannot be saved. Foam pet beds, carpets that stayed wet for days and cardboard boxes are mold reservoirs and are rarely worth the effort to rescue.

For more on how ozone treatment works in living spaces, see our page on residential ozone disinfection.

A Room-by-Room Look at a Pet Business After the Flood

Every pet business is laid out differently, but most share the same types of rooms, and each one has its own weak points after a flood. Thinking room by room helps you understand why a whole-space treatment matters.

Reception and waiting area

This is where customers form their first impression. Fabric chairs, rubber floor mats, display shelves of food and toys, and the bottom of the counter all sit at the level floodwater reaches first. Soft furnishings hold moisture for a long time and quickly develop a sour smell. If the first thing a returning customer notices is mustiness, it colors everything that follows, no matter how clean the treatment rooms are.

Exam rooms and the operating theatre

These rooms usually have smooth surfaces that are easy to wipe, but they are full of awkward places: the gap behind an exam table bolted to the wall, the underside of instrument trolleys, the space behind an autoclave, cable trunking along the floor. Floodwater finds every one of those gaps and leaves silt behind. Fogging is particularly valuable here because the mist settles in places a cloth cannot follow.

Recovery and boarding rooms

Rows of cages create dozens of hidden corners, hinges and trays. Animals spend long hours in these rooms, often while recovering from illness or surgery, so the air quality matters a great deal. Stale odors in a boarding room also stress animals, and stressed animals eat less, sleep less and are more prone to illness. Ozone treatment helps reset the air in these rooms so that new guests are not greeted by the smells of the flood.

Bathing and grooming rooms

Wet rooms are permanently humid, so they were already a favorite place for mold before the flood. After floodwater has backed up through drains, the pipes and traps may still hold contaminated sludge. Clearing drains, scrubbing tiles and grout, and then fogging and ozone treatment give these rooms the best chance of staying fresh once daily bathing resumes.

Storerooms and staff areas

Bags of kibble, cat litter, towels and cardboard boxes absorb water and odor like sponges. Anything that was soaked should be discarded. The room itself then needs the same disinfection and odor treatment as the rest of the building, because a forgotten storeroom can quietly reseed spores into the whole premises through the air-conditioning system.

10 Reasons Vet Clinics and Groomers in Sam Khok Choose WHD

1. Every corner is covered. The fine mist from our disinfection fogging service reaches behind cages and under tables where wiping is impossible.
2. Medical-grade disinfectant. We use Chemgene HLD4H, used in hospitals and veterinary facilities.
3. Mild smell, not harsh fumes. Less stress for animals coming back into the space.
4. Odor removed at the source. Ozone treatment breaks down odor molecules instead of covering them up.
5. Fewer airborne mold spores. This reduces the chance of mold coming back quickly.
6. No chemical residue. Ozone reverts to oxygen after ventilation. Read more about ozone treatment for odors and chemical residue.
7. A team that understands pet businesses. We schedule rooms and timing to minimize disruption to your reopening.
8. Clear safety procedures. You get exact instructions on when animals must leave and when they can safely return.
9. Mosquito control available too. Mosquitoes multiply after floods; add our mosquito spraying service around the building.
10. Confidence you can share with customers. Pet owners can see you have taken hygiene seriously before welcoming their animals back.

Before and After

What Business Owners Tell Us (Example Scenario)

"At first I thought scrubbing the floors with bleach would be enough. But the smell stayed, and the cats we board kept refusing to go into their cages. When the team came in to fog and run the ozone treatment, they explained exactly how long the animals had to stay out. The next morning I walked in and could feel the difference in the air straight away. Customers asked what we had done, because the place felt fresh again."

— Pet hotel owner, Sam Khok (illustrative scenario based on field work)

Aftercare: Keeping Mold From Coming Back

• Ventilate every morning, and run a dehumidifier in rooms that tend to feel stuffy.
• Wipe cages and exam tables between patients or between boarding guests with Chemgene HLD4H spray.
• Wash pet blankets and bedding in hot water and dry them completely in the sun.
• Check regularly for leaks and walls that are still damp, and deal with any new mold spot immediately.
• Consider periodic ozone treatment if heavy daily use causes stale animal odor to build up.
• If your reception area has carpet or upholstered seating, add our dust mite removal service.

Recovery after a flood is rarely a single event. Walls and floor slabs can hold moisture for weeks, so the first month after reopening is when you should be most watchful. A quick daily walk-through, sniffing for mustiness and looking at the lower parts of walls, catches small problems before they become big ones.

Frequently Asked Questions

Q: How long do animals need to stay out during ozone treatment?
A: All animals must leave before treatment begins, and they can only return after the full ventilation period our team specifies. The exact time depends on the size of the space and how severe the odor is. We confirm it with you on the day of the survey so you can plan.

Q: Do animals need to leave for the Chemgene fogging as well?
A: Yes, we recommend moving all animals out for the entire job. It lets the team fog thoroughly and avoids stressing the animals. Wait until surfaces are dry before bringing them back.

Q: What should we do with medicines, vaccines and pet food?
A: Move them out or seal them securely, and store them in an area outside the ozone treatment zone.

Q: Will ozone completely remove mold from the walls?
A: Ozone helps destroy airborne spores and reduce odors, but walls that are still wet or materials that are badly damaged may need repair or replacement. Our team will give you an honest assessment.

Q: Is one treatment enough?
A: In many spaces a single treatment makes a clear difference. If the building is still damp or odors build up from heavy use, a follow-up treatment may be worth considering after the re-check.

Q: Do you serve Sam Khok and other districts of Pathum Thani?
A: Call 065-556-6294 or message LINE @whd268 to check service areas and book a site survey.

Reopen With Confidence. Let WHD Restore Your Space.

Vet clinics, grooming salons and pet hotels in Sam Khok and across Pathum Thani: book your site survey today.

View 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
• All articles

Health reference: World Health Organization (WHO): Floods fact sheet · Thailand Department of Disease Control