A typical scenario (an illustrative situation drawn from common post-flood experiences, not a review from any specific customer)

Twelve days before the wedding, the bride asks to see the room again

Jen is the banquet manager of a mid-sized hotel in eastern Bangkok. Its ballroom sits on the ground floor and seats several hundred guests. It is fully carpeted, its walls are lined with fabric-wrapped acoustic panels, and an operable partition can divide it into three meeting rooms. There is a timber stage, velvet drapes, several hundred upholstered banquet chairs, and a linen store at the back for tablecloths and chair covers. In late September 2026, days of heavy rain hit Bangkok and, according to news reports, the eastern side of the city was hit hardest. Water flowed into the car park and the corridor behind the kitchen, then seeped into the ballroom until almost half the carpet was soaked.

After the water went down, the maintenance team pulled up all the wet carpet, washed the concrete slab and ran fans and dehumidifiers for days. They removed the lower row of acoustic panels that had wicked up water, ordered new carpet laid with adhesive, repainted the exposed wall sections and sanded and re-lacquered the stage edge. Water-affected chairs went out for cleaning. Within two weeks everything looked immaculate, just in time for the October events booked months ahead.

Twelve days before the first wedding after the flood, the couple and the bride's mother came to confirm the seating plan. The moment the ballroom doors opened, the mother stopped and asked what the smell was. The room smelled of new carpet adhesive mixed with paint, and near the linen store there was still a faint mustiness. She explained that several elderly relatives in their eighties would attend, along with small grandchildren and a pregnant bridesmaid, and that guests would sit in this room for three to four hours. Would they be all right? Jen could only say she would run the air-conditioning to clear the smell, knowing that answer reassured no one.

Meeting rooms, banquet halls and event spaces bring many people together for hours in a closed room, and organisers have high standards because it is their important day. This article explains why these spaces have their own post-flood odour problems, why common fixes fall short, and how ozone odour and chemical-residue removal with before/after TVOC readings helps banquet teams answer clients with confidence.

The late-September 2026 Bangkok floods and the events business

According to news reports, roughly 300 mm of rain fell over about 48 hours between 24 and 27 September 2026, flooding large parts of Bangkok. On 26 September the Bangkok Metropolitan Administration declared all 50 districts a disaster zone. The east of the city was hit hardest, with areas such as Khlong Chan and Bueng Kum mentioned. Governor Chadchart said the canals were full and drainage would take two to three days after the rain stopped. As of 30 September, some roads, including Si Burapha and Lat Phrao, still had 20 to 40 cm of standing water.

Thai media compared the event with the 2011 floods, and one Thai business report cited a Chamber of Commerce estimate of about 12,300 million baht in damage. For hotels, convention centres, restaurants with function rooms and wedding venues, the post-flood period brings the hardest decision: postpone events clients have booked, or race to restore the space in time. If they choose the latter, the room must not just look good; the air must let guests sit comfortably for the whole event.

Why banquet halls and meeting rooms hold so much post-flood odour

Large carpets and carpet adhesive

Carpet is one of the most absorbent materials for both water and odour. Carpet soaked in sewage-contaminated floodwater usually has to go, but the smell can linger in the slab beneath. New carpet laid with adhesive, plus new underlay, then releases volatile organic compounds (VOCs) for days. A wall-to-wall carpeted room has a huge emitting surface.

Fabric everywhere

Fabric-wrapped acoustic panels, stage drapes, chair covers, tablecloths and hundreds of upholstered seats all absorb odour from the air. Even pieces that never touched the water can pick up mustiness after days in a closed, humid room. Acoustic panels that wicked water from below also harbour hidden moisture and mold.

Storerooms and back-of-house corridors

Linen stores, chair and table stores, AV equipment rooms and kitchen corridors usually sit on the same level as the function room and have little ventilation. When flooded, their musty air flows into the event space every time staff open the door to bring in food and equipment.

High ceilings and huge air volumes

Ballrooms and large meeting rooms have high ceilings and large air volumes, and opening windows is rarely possible because these rooms are built closed for sound and light control. Air quality depends entirely on the air-conditioning and ductwork. If the ducts have drawn in moisture and odour, every time the system runs it redistributes the smell.

Refit work that must finish before the event

To meet booked dates, teams often repaint, lacquer the stage, install new wall panels and lay new carpet all within days. Emissions from that work are still near their peak when the first guests arrive.

Cleaning chemicals and masking fragrance

After a flood, venues use large amounts of cleaner, bleach and carpet shampoo, and spray fragrance before client viewings. The result is a mix of chemical smells in a big closed room, which can leave some guests with stinging noses or dizziness over a long event.

Who is affected when air quality in a function room is poor

Some VOCs at high concentrations can irritate the eyes, nose and throat and cause headaches, nausea or dizziness, while mold spores and musty air are well-known allergy and asthma triggers. Function rooms carry a particular risk because guests sit in a closed room for hours and every event brings a very mixed crowd. Groups that deserve extra care include:

• Older guests, who are central to weddings, ordination ceremonies, merit-making and anniversary dinners, and usually stay seated throughout.
• Young children, who play close to the carpet, where adhesive and musty odours are strongest.
• Pregnant women, who are often sensitive to smells and are generally advised to avoid paint and solvent fumes.
• People with allergies, asthma or chronic lung disease, whose symptoms can flare in damp or dusty rooms.
• Banquet staff, servers and technical crews, who work in the room from set-up to tear-down, plus staff who helped with the flood clean-up.

For staff who pulled up carpet and cleared mud during the flood: anyone who develops fever, muscle pain (especially in the calves), red eyes, diarrhoea or an inflamed wound after floodwater contact should see a doctor promptly and mention the exposure, as these can be signs of leptospirosis. Ozone treatment and cleaning are not medical treatment and cannot replace medical care.

The business impact on banquet and event venues

Events with no second chance

A wedding, product launch, annual seminar or retirement dinner happens once. If guests remember a strange smell, that memory travels with the photos and videos forever. Disappointed clients rarely rebook and rarely recommend.

Cancellations and postponements

Clients who view the room and feel uneasy may postpone or move elsewhere, which means losing the entire event, including food, beverage and guest-room revenue, just when the business most needs income to recover.

Corporate clients want evidence

Companies holding seminars or conferences often have HR or safety teams that need to know the venue is safe for their staff. "It's been cleaned" may not be enough. A description of the recovery steps plus before/after TVOC readings from calibrated instruments gives procurement and safety teams something concrete.

Reviews and venue image

Hundreds of guests at one event means hundreds of potential reviewers. Comments like "the hall smelled of glue" or "musty after the flood" spread quickly among people searching for a venue.

Very short gaps between events

Most venues run tight calendars, sometimes with a morning and an evening event on the same day. Closing a room for days to let smells fade is rarely an option; odour control has to fit into short windows between bookings.

What venues usually try, and why it isn't enough

Running the AC at full blast for hours beforehand. Most systems mainly recirculate room air, so the room gets cooler but odour molecules are not removed. If the ducts have absorbed smells, this may spread them further.

Spraying fragrance or using scent diffusers before guests arrive. This masks odour temporarily. Two or three hours into the event, the fragrance fades but the adhesive and mustiness remain. Strong fragrance can also clash with the food the chef has prepared.

Shampooing the carpet and relaying it quickly. Carpet soaked in contaminated water for days may look clean after washing, but if the underlay or slab is still damp, mustiness returns within days.

Repainting and re-lacquering the stage, then using the room immediately. The room looks great in photos, but guests breathe paint and lacquer VOCs throughout the event.

Charcoal odour absorbers in the corners. They lack the capacity for a room with thousands of cubic metres of air and fabric on every surface.

WHD ozone odour and chemical-residue removal for meeting and banquet rooms

World Health Disinfection (WHD) provides ozone chemical-residue and odour removal for homes, condos, offices, factories, hotels, storage facilities and many other buildings, including meeting rooms, ballrooms and event spaces. According to the service information, ozone (O3) oxidises odour molecules directly, breaking them apart at the source instead of covering them with fragrance.

According to the service information, ozone targets paint, thinner, epoxy and lacquer odours, VOCs and musty smells, and also helps reduce bacteria, viruses and mold. After the contact time it reverts to oxygen with no residue, and the space is ready to use about 2 hours after treatment. Venues can therefore treat the night before an event or during a gap between bookings and then carry on with set-up as scheduled.

WHD measures TVOC (total volatile organic compounds) with calibrated instruments before and after treatment, so the banquet team has comparable data to share honestly with wedding couples and corporate clients alike. The team uses a Master Ozone Generator suited to large, high-ceilinged rooms.

How the process works in function and event spaces

1. Survey the space and the calendar. The team inspects the function room, breakout rooms, linen and furniture stores, back-of-house corridors and air-conditioning, and reviews bookings to find the right window.
2. Baseline TVOC readings at several points, such as the centre of the room, near the stage, beside acoustic panels and outside storerooms.
3. Room preparation. Food, beverages, fresh flowers, plants and any animals are removed. Linen and equipment store doors are opened, and chair covers or drapes are spread out so ozone reaches all surfaces.
4. Empty and sealed. Ozone treatment is done only in a closed space with no people, pets or plants inside. Warning signs go on every entrance, and building security is informed.
5. Ozone release and contact time with the Master Ozone Generator, matched to room volume and odour level.
6. Rest and ventilation. The space rests while ozone reverts to oxygen. No one enters until the team confirms it is safe.
7. Post-treatment TVOC readings and summary for the banquet team to reference with clients and to plan care before future events.

Ozone treatment comes after removing damaged materials, clearing mud, washing, surface disinfection and drying; it does not replace them. The service helps reduce odour and chemical exposure during recovery. It does not prevent flooding and is not medical treatment.

10 reasons meeting and banquet rooms should be ozone-treated before reopening for events

1. Guests smell the celebration, not carpet glue. Ozone odour removal for banquet halls helps reduce odours from new carpet, adhesive, paint and lacquer.
2. Answer clients with numbers. Before/after TVOC readings from calibrated instruments help couples and corporate clients decide with confidence.
3. It reaches every fabric surface, including acoustic panels, drapes, seat cushions and covers that cannot be wiped.
4. Storerooms and back-of-house are included, the musty sources that flow into the room whenever doors open mid-event.
5. It breaks odour molecules down instead of masking them, so there is no need for strong fragrance that competes with the food.
6. Suited to high ceilings and large volumes, with a Master Ozone Generator built for big spaces.
7. No residue on linens or chairs. Ozone reverts to oxygen once the contact time ends.
8. Ready about 2 hours after treatment, so it can be scheduled between events or the night before without cancellations.
9. It helps reduce airborne bacteria, viruses and mold, supporting hygiene for guests who share a room for hours.
10. It protects your venue's reputation and booked revenue. See details on the ozone chemical-residue removal service page.

Before and after ozone treatment in a banquet hall

Note: results depend on room volume, the starting odour level and how thoroughly the space was cleaned and dried beforehand.

Example case: a small conference centre in an office building on Lat Phrao

Example case (a simulated scenario to illustrate the process, not a testimonial from a real customer)

Wit manages a small rentable conference centre on the ground floor of an office building in the Lat Phrao area. It has one large seminar room, four breakout rooms and a foyer used for coffee breaks. The road outside held water for several days after the rain stopped, and water seeped in through the front doors and floor drains, soaking large areas of carpet in the seminar room and foyer.

The building team removed the wet carpet, washed and disinfected the slab, ran dehumidifiers continuously, then laid new carpet tiles with adhesive and repainted the lower walls. Meanwhile, a corporate client that had booked the seminar room for a two-day staff training emailed to ask whether the venue was safe for its employees and requested information on the flood recovery.

Wit contacted WHD. The team took baseline TVOC readings in the seminar room, two breakout rooms and the foyer, and found the newly carpeted seminar room highest. They scheduled treatment for a Friday night once the carpet adhesive had cured for the period specified by the manufacturer, coordinating with building management to close the area, informing security and posting no-entry signs on every door. After the rest and ventilation period, the team re-measured TVOC at the same points and sent a summary.

Wit attached the recovery steps and the before/after TVOC figures to his reply, which the client's HR team used to confirm the training would go ahead as planned. The lesson: corporate clients want more than verbal reassurance; they want a process they can verify.

Flood-recovery checklist for meeting and banquet rooms

Before booking ozone treatment

• Have an electrician inspect floor boxes, sockets, sound and lighting systems at low level before use.
• Wear rubber gloves, boots and masks while removing carpet and clearing mud.
• Remove soaked carpet, underlay and acoustic panels; photograph everything for insurance.
• Wash the slab and hard surfaces, then disinfect with a suitable product such as Chemgene HLD4H medical-grade disinfectant at the label dilution and contact time.
• Dry the floor thoroughly with dehumidifiers before laying new carpet.
• Send water-affected seat cushions, covers, tablecloths and drapes for cleaning.
• Have an HVAC technician inspect and clean filters and ducts that may have drawn in moisture and odour.
• Finish carpet, paint and stage work, and let adhesives and finishes cure per manufacturer guidance.

On treatment day

• Choose a window when the room is empty for the full treatment and rest period.
• Remove food, beverages, fresh flowers, plants and any animals.
• Open storeroom and linen-store doors and spread out covers so ozone reaches them.
• Seal openings to other areas, inform building management and security, and sign every door.
• No one enters until the team says it is safe.

After treatment

• Ventilate as advised before starting table set-up and decoration.
• Control humidity in the room and storerooms and check mold-prone spots regularly over the following weeks.
• Use room fragrance sparingly so it neither competes with food nor triggers allergies.
• Keep the TVOC summary and photos to answer clients who come for viewings.

FAQ: ozone treatment for meeting and banquet rooms after a flood

Can ozone reach every part of a high-ceilinged ballroom?

Yes. The team uses a Master Ozone Generator and calculates based on the actual room volume measured during the survey. Very large rooms can be zoned using the operable partitions.

How far ahead of an event should treatment be done?

According to the service information, the space is ready about 2 hours after treatment, so many venues treat the night before or during a gap between events. The team confirms total timing after the survey.

Can chairs, linens and AV equipment stay in the room?

General furniture and fabrics can stay, and keeping them in the room means odours trapped in them are treated too. The team advises on specific equipment or materials case by case during the survey.

Should we treat before or after laying new carpet?

After, once the adhesive has cured for the manufacturer's specified period, because carpet adhesive is a major VOC source that appears after installation.

Can ozone replace removing sewage-soaked carpet?

No. Saturated materials that cannot be properly cleaned and dried should be removed. Ozone comes only after cleaning and drying.

Is there documentation for corporate clients?

WHD measures TVOC with calibrated instruments before and after treatment and provides a summary the venue can use when communicating with clients.

A staff member who removed carpet feels unwell. What should we do?

If they have fever, calf pain, red eyes or diarrhoea after floodwater contact, they should see a doctor promptly and mention the exposure. Ozone treatment is not medical treatment.

Keep every booked event on track, in a room guests enjoy from start to finish

WHD can survey your meeting rooms, banquet halls and event spaces, measure TVOC and schedule ozone treatment around your event calendar.

Book a Venue Survey and Ozone Treatment

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

Related links

• Ozone chemical-residue and odour removal service
• Residential and building ozone disinfection
• Chemgene HLD4H medical-grade disinfectant

References

• 2026 Bangkok floods (Wikipedia)
• Al Jazeera: Disaster zone declared across Bangkok
• CDC: Floods
• WHO fact sheets