A typical scenario (an illustrative situation drawn from common flood recoveries, not a review from any specific agency)

Opening morning: villagers are waiting at the door, but the service hall still smells damp

A Subdistrict Administrative Organisation (SAO, known in Thai as an "Or Bor Tor") in Warin Chamrap district, Ubon Ratchathani, sits close to the Mun River. In a year when the floodwater arrived earlier and faster than usual, the single-storey office building went under almost a metre of water and stayed flooded for weeks. Meanwhile, the SAO's assembly hall, standing on slightly higher ground, became a temporary shelter and a relief distribution point. Hundreds of villagers came and went each day to sleep, eat and collect relief bags.

When the water receded, Somsri, the SAO's chief administrator, worked with her staff and volunteers to shovel out mud, wash the floors, wipe down the service counters and drag the waiting-area chairs out into the sun. Everyone wanted to reopen as quickly as possible. Residents needed to file claims for disaster assistance, request certificates, register for the elderly living allowance and deal with all the civil registration work that had piled up during the flood.

On the first morning of service, several older residents sat waiting their turn in a room that still smelled musty. Some ceiling tiles had begun to show black spots, and a tide line marked the lower walls. Two staff members had started coughing and sniffling within a few days of returning to work. The assembly hall that had served as a shelter still reeked of sweat, food and the damp mattresses that had only just been carried out. Somsri began to ask herself whether a building that looked clean was really safe enough for the dozens of people who would walk through its doors every day.

Why flooded public offices carry their own special risks

Local government buildings, such as SAO offices, municipal offices, district offices and one-stop public service centres, differ from homes and private offices in several ways. First, a wide cross-section of people passes through every day: older adults, people with disabilities, pregnant women, parents carrying small children and people with chronic illnesses coming in about welfare. Second, there are many shared touch points: counters, pens tied to the form desk, queue-ticket machines, chair armrests, restroom door handles and ID card readers. Third, after a flood, public buildings are often used as shelters or donation centres, so large numbers of people share the same spaces for extended periods.

The organisms to watch in a public service building

Mold in ceilings, partition boards and furniture. Many government buildings use gypsum ceilings, board partitions, plywood cabinets and upholstered chairs. These materials soak up water and humidity. After several damp days, molds such as Aspergillus, Penicillium and black molds grow and release spores into the air. People with allergies, asthma or weak lungs may suffer coughing, sneezing, congestion, breathing difficulties or eye irritation.

Bacteria and viruses on shared touch points. Mud and sewage-contaminated floodwater carry enteric bacteria such as E. coli into the building. When many hands touch the same surfaces, germs can travel to hands, mouths and food, causing diarrhoea, stomach cramps and vomiting. The weeks after a flood are also a time when respiratory viruses spread easily in crowded places like shelters and waiting rooms.

Musty odours and decaying organic matter. A musty smell is more than a nuisance. It signals that moisture and microbial activity are still present in materials, especially in halls where mattresses, food and waste accumulated.

Risks from wading. Staff and volunteers who waded through water while moving documents or distributing supplies may have been exposed to leptospirosis from water contaminated by animal urine. Anyone with fever, headache or calf pain after wading should see a doctor promptly, as Thailand's Department of Disease Control regularly advises during flood seasons.

Who is most at risk if the office reopens too soon

The first group is older residents who come to register for allowances or request help. They often wait a long time and many have underlying conditions. The second group is young children who come with their parents, touch everything and put their hands in their mouths. The third is pregnant women seeking welfare services. The fourth is people with chronic illnesses or disabilities. The last group, often forgotten, is the staff themselves, who spend eight hours or more a day in the building during the busiest period of the year.

What an agency pays if the building is not truly ready

Health of citizens and staff. If several staff members fall ill at once, the very services people need most after a flood grind to a halt. Citizens who visit and then fall sick are unlikely to want to come back.

Budget. Quick fixes such as painting over mold, followed by tearing everything out again a few months later, mean paying twice. After a flood, local budgets are needed for many urgent forms of assistance to residents.

Time and service continuity. Flood-affected residents need to submit their assistance claims before deadlines. If an office opens late, or has to close again because of building problems, residents' rights and livelihoods suffer directly.

Image and public trust. Government agencies are where people turn in a crisis. A building with musty odours and visible mold does not inspire confidence. A clean, airy and safe building sends a clear message that the local authority is ready to help the community return to normal.

Staff families. Most local officials live in the area, and their own homes were often flooded along with everyone else's. If they go home sick, they may pass illness on to children and elderly relatives.

Why the usual approach is not enough

Washing the floor, wiping the counter and reopening straight away. Washing is an essential first step, but mold hidden above the ceiling, behind partition boards, in cable ducts and inside chair cushions keeps releasing spores. A room that looks clean on day one smells musty again the next week.

Pouring strong bleach throughout the building. Bleach has its uses on some hard surfaces, but excessive concentrations irritate staff airways, corrode metal, discolour materials and cannot reach the air or sealed voids. Mixing bleach with certain toilet cleaners can also release dangerous gases.

Switching the air conditioning on immediately to make the room comfortable. Units whose coils or drain lines are dirty with moisture and mud dust can spread spores and odours around the room. Have a technician clean and check them first.

Repainting over mold stains to make walls look new. This helps appearances for a while, but mold under the paint is still alive. It often makes paint blister or reappears as black spots, and the repairs have to be paid for again.

Spraying air freshener or burning incense to hide the smell. Fragrance may feel better for a moment, but it does not remove the cause and can trigger reactions in people sensitive to chemicals or smoke.

WHD ozone disinfection: the step that lets you reopen to the public with confidence

World Health Disinfection (WHD) provides a Residential and Building Ozone Disinfection service for homes, condominiums, hotels, offices, schools, hospitals and factories, which includes government office buildings and public service centres.

Ozone (O3) is a strongly oxidising gas. Released in a sealed room, it spreads throughout the entire space, including above the ceiling, under desks, inside cabinets and into the fabric of upholstered chairs. It destroys the cell structures of viruses, bacteria and molds and breaks down the molecules that cause musty odours, then reverts to oxygen (O2) without leaving chemical residue. According to the test results certified for the company by Thailand's Department of Medical Sciences and Intertek (UK), the WHD system eliminates 99.99% of viruses, bacteria and mold.

Important: ozone treatment comes after mud removal, washing and drying. It does not replace cleaning, removing damaged materials or repairing electrical systems, and it is never a substitute for medical care for anyone who is unwell.

How the work is carried out in a government building

1. Survey and plan with the agency. The team surveys service areas, offices, meeting rooms, the assembly hall, restrooms and storage rooms, then divides the building into zones and schedules work at times that will not disrupt services, such as evenings or official holidays.
2. Coordinate supporting documents. The team can prepare a description of scope, areas and steps for the agency to use in its own procurement consideration.
3. Prepare the space. The area must already be washed and dried. Food, drinking water, medicines and plants are removed, important documents are locked in cabinets and windows and doors are closed.
4. Everyone leaves. Treated rooms must be completely empty of staff, members of the public, pets and plants. "No entry" signs go up and someone is assigned to watch the entrance.
5. Release ozone. Equipment is matched to room size. A cycle typically takes about 30 minutes per zone, depending on size and condition.
6. Contact time. Ozone is allowed to work on microbes and odours in every corner.
7. Rest and ventilate. The space is left while ozone reverts to oxygen, then doors and windows are opened for the ventilation period the team recommends before staff go back in.
8. Hand over. The team reports which areas were treated and gives advice on ongoing care so the agency can reopen with confidence.

A risk map of the public office: where to start

Service counters and waiting areas. This is where citizens spend the most time. Upholstered chairs, wooden counters and partitions absorb moisture. Make this the first zone that must be ready before reopening.

Public restrooms. Usually on the ground floor and the first place sewage backs up. Remove every trace of waste, check the drains, then disinfect and apply ozone to deal with odours trapped in gaps and joints.

Assembly halls and multipurpose rooms used as shelters. These accumulate odours and germs from heavy shared use. Remove all mattresses, blankets and rubbish, wash the floor and any temporary kitchen, then treat the whole room with ozone.

Staff offices and supply rooms. These tend to hold plywood cabinets, paper files and cartons that feed mold. Remove damaged items and arrange the room so air can circulate before ozone day.

Complaint centres and small meeting rooms. Air conditioners are often left off during the flood and smell musty from the cooling coil when switched back on. Clean the units first, then use ozone to deal with odours trapped in curtains and carpets.

Planning a phased reopening

Few local agencies can close every room at once, and residents cannot wait weeks for services to resume. A phased plan works better. Start with the zone citizens need first, usually the registration and welfare counters plus the nearest public restroom, and bring it back into service as soon as it has been washed, dried and treated. While that zone serves the public, staff can continue clearing offices and storerooms behind the scenes, and the team can return in the evenings to treat the next zone. Post a simple notice at the entrance showing which services are open and where, so older residents do not have to wander through areas still under repair. Keep a short log of what was done in each zone and on what date. It helps with internal reporting, answers questions from the public, and makes the next flood season easier to plan for, because the agency will already know which rooms flood first and which materials failed.

10 reasons SAOs, municipalities and public service centres should use ozone before reopening

1. Protect vulnerable visitors. Older adults, children, pregnant women and people with chronic illness are the main service users after a flood.
2. Reach germs where wiping cannot, above ceilings, behind partitions and inside waiting-room cushions, with our building ozone service.
3. Break down musty odours at the source, so service halls and assembly rooms smell fresh again.
4. No chemical residue, which suits rooms used all day by the public and by staff.
5. Quick turnaround. Around 30 minutes per zone, and work can be done outside office hours.
6. Ideal for halls that served as shelters, helping deal with odours and germs left by heavy shared use.
7. Tested by credible bodies, according to the test results certified for the company by the Department of Medical Sciences and Intertek (UK). See the certification documents.
8. Avoid paying twice. Dealing with microbes before redecorating or repainting reduces the chance of having to tear work out later.
9. Pairs with surface disinfection. Ozone jobs of 15,000 baht or more receive a free medical-grade disinfectant spray for wiping shared touch points every day.
10. Build community confidence. Residents can see the office is ready to serve them safely. Talk to us via the ozone disinfection service page.

Example case: a subdistrict municipality office in Sukhothai

Example case (an illustrative scenario to explain the process, not a verified review)

Wichai heads the administrative office of a subdistrict municipality on the Yom River in Sukhothai. Floodwater filled the ground floor, which houses civil registration and welfare counters. The upper floor holds executive offices and a meeting room, which during the flood became a coordination centre and a store for donations, with volunteers coming and going day and night.

After the water went down, the municipality followed a clear sequence. An electrician inspected the entire system. Mud was shovelled out and floors were washed with cleaning solution. Swollen ceiling boards and the wet lower sections of partition walls were removed. Fans and dehumidifiers ran for several days until materials were dry, and every air conditioner was cleaned. Only then did the municipality book the WHD team to apply ozone over a holiday, zone by zone: the ground-floor service area, the public restrooms, the upstairs meeting room and the storeroom.

Wichai says the most obvious change was the smell in the service hall, and the way staff felt comfortable sitting at their desks all day again. The other lesson was that working in order avoided paying twice. If they had painted before dealing with moisture and mold, they would almost certainly have had to do it all again.

Recovery checklist for flooded government buildings

Before cleaning begins

• Cut power to flooded sections and have a qualified electrician inspect before switching back on.
• Photograph damage in every room as evidence for reports and budget requests.
• Provide protective gear for staff and volunteers: boots, rubber gloves, masks and eye protection.
• Separate wet official documents and handle them according to your records management rules.

During cleaning and drying

• Remove all mud, wash surfaces with a cleaning solution, then disinfect.
• Remove ceilings, partitions, carpets and cushions that stayed wet too long to dry in time.
• Dry everything as fast as possible, following general public health advice to clean and dry within 24 to 48 hours to limit mold.
• Clean air conditioners before switching them on.
• Never mix bleach with products containing ammonia or acids.

On ozone day

• Remove food, drinking water, medicines and plants, and lock documents away.
• Inform every section and post closure times for the public in advance.
• Everyone leaves the treated area and returns only after the rest and ventilation period.

After reopening

• Set up handwashing points or alcohol gel at entrances and counters.
• Wipe shared touch points such as pens, queue machines and armrests several times a day.
• Open windows regularly and watch for returning odours or mold spots.
• If staff or volunteers develop fever, calf pain or diarrhoea, send them to a doctor quickly.

Frequently asked questions

1. How long does the office need to close for ozone treatment?

Typically about 30 minutes per zone plus the rest and ventilation period. Most agencies schedule the work in the evening or at a weekend, so public service hours are barely affected.

2. Will official documents in cabinets be damaged?

We recommend keeping important documents in closed cabinets or sealed boxes and dealing with wet documents separately according to your rules first. The team will advise on preparation during the survey.

3. If we use ozone, can we skip washing or removing ceilings?

No. Ozone is a step after washing and drying. Materials that are swollen or heavily moldy must be replaced. Ozone helps deal with microbes remaining in the air and in places hands cannot reach.

4. Can staff or the public stay in the room during treatment?

No. Treated rooms must be empty of people, pets and plants and may be re-entered only after the rest and ventilation period the team specifies.

5. Does it work for assembly halls and large buildings?

Yes. The team divides large spaces into zones and chooses equipment suited to the volume, including restrooms and kitchens used while the building served as a shelter.

6. What information does an agency need to request a quotation?

Approximate floor area, number of rooms, type of damage and convenient dates. The team can prepare a scope-of-work description for the agency to use in its own procurement process.

7. What if staff fall ill after helping with flood work?

They should see a doctor and mention their flood exposure, especially with high fever, headache, calf pain or diarrhoea. Ozone treats buildings, not illness.

Make your office a safe place for the community to turn to

Talk to WHD about a post-flood ozone plan for your government building so you can reopen to the public with confidence.

Request an Ozone Quotation for Your Agency

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

Related services and reading

• Residential and Building Ozone Disinfection
• Disinfection services for buildings and agencies
• Certification documents
• Contact us

References

• CDC: Floods and Your Health
• Department of Disease Control, Thailand