A Story From the Field: The First Morning After the Water Went Down

"Khun Sunanta" manages resident care at an elderly care home run by a charitable foundation in Bang Khae district, on the Thonburi side of Bangkok. Around seventy older people live there. Nearly thirty of them are bedridden or use wheelchairs full time. The home is made up of two two-storey buildings joined by a covered walkway. The ground floor holds the shared dormitory for residents who cannot manage stairs, the dining hall, the physiotherapy room and the linen store.

In early October 2026, after several days of heavy rain, water from a nearby canal spilled into the grounds and rose to about a foot inside the buildings. It stayed for almost four days. Staff and volunteers worked through the night to carry bedridden residents upstairs to the second-floor hall, which quickly became crowded with mattresses, wheelchairs and medical equipment. A few residents went to stay with relatives. When the water finally drained away, everyone wanted the same thing: to get the residents back into their own beds as soon as possible.

Then Khun Sunanta walked down the stairs. The musty smell, mixed with a sewer odor, reached her before she reached the bottom step. The dormitory walls carried a brown tide line of mud at the height the water had reached. Black specks of mold were appearing in the corners and behind the storage cabinets. Several pressure-relief mattresses that had been left on the ground floor were heavy with water. The grab rails in the bathrooms were coated in silt, and the exercise mats in the physiotherapy room had started to smell. Upstairs, some residents had begun to cough, and others were sleeping badly in the hot, crowded hall.

The questions she and the foundation's board faced were very direct. How do you disinfect the ground floor and deal with the mold while older people are still living in the same buildings around the clock? Can ozone be used at all if not everyone can be moved out? And how do you make sure that residents with weak immune systems come back to a space that is genuinely clean, not just one that looks dry? This article brings together the approach the World Health Disinfection (WHD) team uses for this kind of job.

Why an Elderly Care Home Is Harder Than an Ordinary House

• Residents cannot simply all leave. A family can lock up a house for a day while it is ozone-treated. A care home has people who need help twenty-four hours a day. The work has to be planned zone by zone, with clear boundaries between areas being treated and areas where people are living.
• Residents are more vulnerable. Many older people live with diabetes, chronic lung disease, heart conditions or pressure sores. Their bodies are less able to fight off germs, and they react more strongly to mold spores and dust.
• A great deal is shared. Wheelchairs, walking frames, canes, grab rails, shower chairs, adjustable beds and dining tables are used by many people every day. If any of these are missed, germs can move easily from one resident to the next through hands.
• There is a lot of fabric. Bed sheets, blankets, draw sheets, pressure-relief mattresses and pillows soak up water and hold musty odors better than anything else in the building, and the home needs a full supply every single day.
• Visitors and donors notice. Relatives, volunteers and donors come and go every week. The smell and cleanliness of the building speak directly to the trust people place in the foundation.
• Budgets are tight. Most foundations rely on donations and must spend them carefully. Doing the job properly once is far better value than trying several methods that do not work.

Because of all this, the usual "clean the whole house in a day" approach simply does not fit. What a care home needs is a plan that respects the daily rhythm of care, keeps residents well away from any treatment, and still reaches every corner where moisture and mold are hiding.

Health Risks for Older Residents

The following is general information, not medical advice. Care for each resident should follow the guidance of the doctors, nurses and health team responsible for them.

• Breathing: Mold spores and dust from dried mud can make older people cough, feel short of breath, or experience worse symptoms of chronic lung disease and asthma. Bedridden residents spend all day close to floors and walls, so they are exposed more than anyone else.
• Skin and pressure sores: Mattresses and linens that are still damp or contaminated may raise the risk of skin irritation and infection in existing wounds.
• Diarrhea and stomach infections: A dining hall, food preparation area or tableware that was under floodwater may harbor organisms that cause diarrhea. In older people, diarrhea can lead to dehydration quickly.
• Leptospirosis: This infection spreads through floodwater and rat urine. Staff and volunteers cleaning mud should wear boots, gloves and masks, and keep any cuts away from water and mud.
• Stress and poor sleep: Being moved suddenly and sleeping in a crowded room leaves some older people confused, anxious or unable to sleep. Returning them safely to familiar surroundings is important for their wellbeing, not just their physical health.

For more on flood-related illness and health after the water recedes, see the Thai Department of Disease Control, the Department of Health and the WHO fact sheet on floods.

Why Common Fixes Fall Short in a Care Home

• Pouring strong bleach everywhere. The sharp chlorine smell can make breathing harder for residents with lung conditions, and bleach does not reach mold that has soaked deep into walls or mattresses.
• Drying with fans. Fans lower surface moisture, but if walls already have mold, moving air carries spores throughout the building, including to the floor where residents are staying.
• Air freshener sprays. They mask the smell for a few hours, and strong fragrances can bother older people who are sensitive or allergic.
• Painting over mold stains. Fresh paint hides the marks for a while, but the moisture inside the wall remains, and mold soon grows back underneath.
• Cleaning floors but not equipment. Wheelchairs, walking frames, grab rails and adjustable beds that were in the water are touched by residents' hands every day. If they are not disinfected, the room is not truly clean.
• Bringing residents back before walls and floors are dry. Moisture left behind lets mold return quickly, and residents may have to be moved upstairs a second time, which is exhausting for everyone.

What works is a clear order of work, zone by zone: clear all mud, sort mattresses and linens, get walls and floors genuinely dry, disinfect surfaces and equipment, and only then ozone-treat each zone once it is sealed and empty.

The Solution: Zone-by-Zone Disinfection and Ozone Treatment, Planned With the Nursing Team

WHD provides a professional disinfection service using CHEMGENE HLD4H applied with ULV fogging equipment. The fine mist reaches wall joints, floor edges, the space under beds and behind cabinets. The disinfectant does not have the harsh smell of chlorine, which makes it well suited to buildings where older people live. This is combined with our ozone treatment service, which helps destroy mold spores and break down odor molecules in the air and in materials. Ozone is used only inside zones that have been sealed off and that nobody is in.

Zoning Principles for Care Homes

• Divide the buildings into zones that can be closed off. For example: the left side of the ground-floor dormitory, the right side, the dining hall, the physiotherapy room and the linen store. Each zone must have doors that close, vents that can be sealed, and air conditioning that can be isolated from other zones.
• Residents always stay well away from the zone being treated. During ozone treatment, residents, staff and volunteers must be in a separate building or floor with no shared airflow. If the buildings are so connected that zones cannot be separated, it is better to choose a day when residents can be moved elsewhere temporarily.
• Work follows the nursing team's schedule. Timings are planned around meals, medication rounds and repositioning of bedridden residents. The home's nurses decide where each resident will stay during the work.
• Medical equipment comes out first. Oxygen cylinders, oxygen concentrators, suction machines and other medical equipment are moved out of the zone by the nursing team before work begins, and cleaned according to the manufacturer's instructions.
• Product information is shared openly. The nursing team or board can request product information in advance to help them make decisions.

How the Work Proceeds

1. Joint survey and planning. We inspect the dormitories, dining hall, bathrooms, physiotherapy room, linen store and drainage with the manager, the nursing team and the facilities staff, and agree the order of zones and the dates and times.
2. Advice on mud clearance and sorting. Pressure-relief and foam mattresses soaked by floodwater usually need replacing. Washable sheets and blankets should be washed hot and dried completely. We advise on flushing mud from wall edges, under beds and out of drainage channels.
3. Moving residents and equipment. The nursing team moves residents and medical equipment out of the zone to be treated, and the connecting corridor is closed off.
4. Chemgene HLD4H fogging. We fog floors, walls, under beds, bedside cabinets, grab rails, bathrooms, shower chairs and drains, and wipe or fog the wheelchairs and walking frames that have been gathered together.
5. Controlled ozone treatment, one zone at a time. The zone is sealed, warning signs go up and the generator runs for a period suited to the size of the space, targeting mold and odors embedded in walls, ceilings and air.
6. Ventilation. Doors, windows and exhaust fans are opened, and we wait until the ozone has broken down into oxygen before anyone goes back in.
7. Re-check and hand-back. We check odor and the spots where mold had appeared. Once floors and walls are dry, the nursing team brings beds and residents back into the zone, and work moves on to the next one.

10 Reasons Bang Khae Care Homes Choose Professional Zone-by-Zone Restoration

1. Residents don't all have to leave, because the work runs zone by zone on a plan agreed with the nurses.
2. Dormitories and bathrooms are disinfected thoroughly by a disinfection service using fine mist.
3. Mold and musty odor are tackled at the source with ozone treatment, not just masked.
4. A disinfectant without a harsh smell, CHEMGENE HLD4H, suits residents who are sensitive to odors.
5. Wheelchairs, walking frames and grab rails are included, the shared touch points used every day.
6. No clashes with the care routine, including meals, medication rounds and repositioning.
7. Lower exposure to mold and mud dust for residents with lung disease or weak immunity.
8. Residents return to familiar beds sooner and safely, easing the stress of crowded temporary rooms.
9. A clear work record for the board and donors, showing donations were used well.
10. Easy to extend into long-term care, such as dust mite removal for mattresses and mosquito spraying around the grounds after the flood.

Before and After Restoring the Care Home

A Customer's Voice (Illustrative Scenario)

"What reassured us was that the team didn't tell us to move every resident out. They sat down with our nurses and worked out which zone to do first, when meals were served and when residents needed turning. One of our bedridden grandmothers was back in her own bed within a few days, and relatives who came to visit told us the room didn't smell musty anymore."

— Khun Sunanta (pseudonym), resident care manager at a foundation-run elderly care home in Bang Khae

Checklist for Managers and Nursing Teams

Restoring a care home touches nursing, kitchen, facilities, administration and families all at once. This checklist helps keep everyone aligned from the first survey to the day the last zone reopens.

• List residents by level of dependency: who can walk, who uses a wheelchair, who is bedridden. This makes it much easier to plan moves for each zone.
• Tell relatives in advance about temporary room changes and any changes to visiting arrangements.
• Decide which pressure-relief mattresses, pillows and cushions must be replaced, and order new ones to arrive after that zone is fully dry.
• Gather wheelchairs, walking frames and shower chairs in one place so they can be cleaned and disinfected together.
• Check the food preparation area, tableware and refrigerators, and throw away any food that was touched by floodwater.
• After reopening, set a routine for wiping grab rails, door handles and wheelchair armrests with Chemgene disinfectant spray.
• Keep a record of what was done, when and in which zone, for the board, donors and the authorities that oversee the home.

Communication matters as much as cleaning. A short note to families, a briefing for night-shift staff and a simple timetable posted at the nurses' station help everyone understand what is happening, where residents are staying and when each zone will reopen.

Making the Temporary Upstairs Arrangement Safer While You Wait

Restoration takes days, not hours, and during that time residents are often living in crowded temporary spaces. A few practical steps make those days safer and calmer while the ground floor is being restored.

• Space out beds and mattresses where you can. Even a little extra distance between residents makes it easier for staff to reach each person, reposition them and keep the floor around them clean.
• Keep the temporary room aired. Open windows when the air is not too humid and use fans to move fresh air through the room, as long as the room is not connected to a zone being treated.
• Set up a clean handwashing point. If the nearest bathroom is on the flooded floor, set up a temporary handwashing station with soap, clean water and paper towels for staff and visitors.
• Keep dirty and clean separate. Mark a clear place for soiled linens and a separate place for clean linens, so that nothing used is accidentally put back on a bed.
• Watch residents closely. Crowding, heat and disrupted routines can affect older people in ways that are easy to miss. Nurses may want to check temperature, fluid intake and breathing more often than usual, following their own clinical judgment.
• Limit traffic. Ask visitors to keep visits short during this period and keep volunteers who are cleaning mud downstairs away from the resident area until they have washed and changed.

Thinking about the temporary space as part of the restoration plan, not just a holding area, helps the nursing team stay in control and avoids rushing residents back downstairs before their rooms are truly ready.

Keeping Mold From Coming Back After Residents Return

The rainy season in Bang Khae does not end the day the floodwater drains away. Humidity stays high for weeks, and a dormitory with dozens of residents, plenty of linens and many mattresses is exactly the kind of space where musty odors and mold can return. A few simple habits help the results last.

• Open windows for ventilation in the late morning when the sun is out and the air is drier, and run bathroom exhaust fans after residents are bathed.
• Dry sheets and blankets completely before putting them away. Never store linens that are still slightly damp.
• Vacuum mattresses and pillows regularly, or book a periodic dust mite removal service.
• Check corners, behind cabinets and under beds every week. If dark spots or a musty smell return, deal with them early.
• If the building flooded badly, consider a follow-up ozone treatment a few weeks later, still done zone by zone, to keep odors and mold under control through the rest of the wet season.

Giving one named staff member responsibility for these checks, with a simple weekly sheet to tick off, keeps them from slipping when the home gets busy.

Frequently Asked Questions

Q: Can ozone be used in a building where residents are still living?
A: Only in zones that can be completely sealed off and that nobody is in, with no airflow or air conditioning linking them to occupied areas. If zones cannot be separated, residents should be moved somewhere else temporarily.

Q: Can a flooded pressure-relief mattress still be used?
A: Mattresses where floodwater has soaked into the core usually need replacing, because they are very hard to dry fully and become a source of mold. For mattresses with waterproof covers where water did not reach the core, ask the manufacturer how to clean them.

Q: How long before residents can return to a zone?
A: Disinfection and ozone treatment for each zone can usually be completed in one day including ventilation, but residents should return only once floors and walls are dry.

Q: Will the disinfectant affect residents with allergies?
A: The team works only in zones with nobody inside, and waits for surfaces to dry and air to clear before handing the zone back. The nursing team can request product information in advance.

Q: How are wheelchairs and medical equipment handled?
A: Wheelchairs and walking frames can be cleaned and their surfaces disinfected. Medical equipment is removed by the nursing team beforehand and cleaned according to the manufacturer's instructions.

Q: Do you work with privately run nursing homes too?
A: Yes. The same zone-by-zone principles apply to private nursing homes, day care centers for older people and assisted living buildings.

Q: Which areas do you serve?
A: All of Bang Khae district, including Bang Khae, Bang Khae Nuea, Bang Phai and Lak Song, as well as nearby areas such as Phasi Charoen, Nong Khaem, Thawi Watthana and Bang Bon.

Give Residents a Clean, Safe Dormitory Again

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

Related Articles and Links

• Ozone disinfection for residences
• CHEMGENE HLD4H disinfectant
• Dust mite removal service
• All articles
• External sources: WHO: Floods and health and the Thai Department of Health

#CareHomeDisinfection #PostFloodDisinfection #DisinfectionService #OzoneTreatment #MoldRemoval #MustyOdorRemoval #Chemgene #BangKhaeElderlyCare

Keywords: elderly care home disinfection after flood, nursing home ozone treatment, foundation elderly home flood recovery, mold removal dormitory, musty odor removal, Bang Khae, Bangkok 2026