Flooding on Rattanathibet Road, Nonthaburi, 2026 (B.E. 2569)

According to The Bangkok Insight, at about 15.30 on 26 September 2026 (B.E. 2569) heavy rain flooded the road surface of Rattanathibet Road from the Nonthaburi Government Center to Khae Rai intersection to a depth of about 15 to 20 centimetres, and Nakhon Nonthaburi Municipality advised small vehicles to avoid the route (source: The Bangkok Insight, 26 Sep 2026).

Nationally, Department of Disaster Prevention and Mitigation (DDPM) data as of 06.00 on 7 October 2026 (B.E. 2569), published by the Government Public Relations Department (PRD), showed 27 provinces plus Bangkok affected, covering 123 districts and 984 subdistricts, with 1,154,875 households and more than 3.1 million people affected (source: PRD, DDPM data as of 7 Oct 2026).

Rattanathibet is a major road lined with office buildings, shophouses, shops, clinics and government offices. Even a few dozen centimetres of water on the road matters, because passing traffic pushes waves onto the pavement and into shopfronts, and the water carries dust, oil, litter and drain water with it. For buildings whose ground floor sits level with the sidewalk, the damage is less about depth and more about the dirt left behind and how often it happens again during the rainy season.

Example Case: A Three-Unit Shophouse That Is Both Office and Shopfront

Note: this is a typical scenario based on situations commonly seen in commercial buildings on main roads after heavy rain. It does not describe any specific person or company.

Nid is the office manager of a mid-sized accounting firm that rents three adjoining shophouse units near Rattanathibet Road. The ground floor holds the customer counter and a small meeting room; upstairs, about thirty staff work at their desks. Behind the building is a narrow alley used for bins, the electrical cabinet and staff motorbikes.

On the afternoon of the heavy rain, water on the road kept rising. Cars pushed waves into the shopfront, and at the same time the drain behind the building backed up, sending black, foul-smelling water into the alley. Staff carried files and computers upstairs, but water still reached the ground-floor tiles and the storeroom.

By the next morning the water had gone, leaving a thin film of mud across the floor, along the skirting and under the counter. The back alley still held litter and sewage stains. A musty smell was drifting upstairs. Two cleaners could mop inside with an ordinary floor cleaner, but nobody had clear responsibility for the frontage or the alley. Staff began asking, "Will the office be disinfected before we come back in?" while customers walked past the frontage every day.

The worrying part was that this was not a one-off. In the 2026 rainy season heavy rain fell again and again, and every time water waited to drain the building team had to start over. Nid began to think the building needed its own equipment, ready every time, rather than hiring outside help for each event.

Why a Few Centimetres of Street Water Is a Building Hygiene Issue

Many people assume ankle-deep water is nothing to worry about. In a city, though, rain flooding often mixes with drain water that carries discharge from restaurants, toilets and neighbourhoods. When drains cannot cope, that water flows back up onto the road and into alleys before entering ground floors.

Bacteria from sewage and drains

Water mixed with sewage may contain E. coli and Salmonella, which are linked with diarrhoea and food poisoning. Standing water and mud contaminated by rat urine in drains and alleys may carry a risk of Leptospira, the cause of leptospirosis. People who wade through water or wash alleys without boots, especially with cuts on their feet, should be careful, and anyone who develops high fever, headache or calf pain after wading should see a doctor.

Viruses in shared spaces

Offices are shared by many people every day. Reception desks, lift buttons, stair rails, meeting rooms and pantries are all common touch points. Gastrointestinal viruses such as norovirus and rotavirus spread easily via surfaces and hands, while respiratory viruses such as influenza and RSV often rise in the rainy season. Cleaning and disinfecting common areas after a flood helps reduce the chance of illness spreading through the workplace.

Mould in walls, carpets and archives

Offices tend to have carpet, ceiling boards, partition walls and boxes of paper files, all of which absorb moisture. If they get wet and do not dry within one to two days, mould begins to grow, causing musty odours and possibly triggering allergies, especially in air-conditioned rooms with little fresh air.

It is worth repeating: the sprayer only spreads the disinfectant. Disinfection results come from the product you choose, the correct dilution and the label contact time, and everything must start with removing the mud.

The Problems Offices and Commercial Buildings Face After the Water Drains

Business cannot stop

Offices must serve customers every day and staff must arrive on time. Cleaning and disinfection usually has to be done in the evening or overnight, within a few hours, not several days.

Unclear responsibility

The frontage, back alley and shared car park often belong to nobody in particular, yet they are where sewage residue collects most. An owner with equipment ready can look after the surroundings without waiting.

Floods recur

Urban rain flooding can happen several times in one season. Hiring help every time may not be fast enough, and doing everything by hand every time costs a lot of labour.

Image with customers and tenants

A customer who walks in to a musty smell or mud along the skirting senses immediately that the place is not ready. Tenants also expect the owner to manage common areas professionally.

Staff health and sick leave

When several staff fall ill at once, the whole organisation slows down. Reducing hygiene risk after a flood also protects business continuity.

Why Ordinary Floor Cleaner and Pump-Up Sprayers Are Not Enough

Mops, cloths and spray bottles remain essential for scrubbing and wiping touch points. But for spreading disinfectant evenly over large areas such as sidewalks, alleys, car parks and several units' worth of ground floor, they fall short.

• Floor cleaner is not always a disinfectant. Many products are made for cleaning and fragrance, not registered for disinfection.
• Pump-up sprayers are slow and tiring. They need constant pumping, produce large drops and do not reach far.
• Gaps are hard to reach. Under shelving, behind electrical cabinets, beside bins and in drain channels.
• Not done before opening time. Doing everything by hand in one night often leaves the job unfinished or patchy.

A motorised backpack mistblower uses fan-driven air to carry droplets far and spread them well, making it suitable for large and outdoor areas around a building and helping the team finish within a limited window.

The SOLO PORT 423: Building Equipment for Large-Area Disinfection

The SOLO PORT 423 is a motorised backpack mistblower from SOLO Kleinmotoren GmbH, Germany, sold in Thailand by World Health Disinfection (WHD) for government agencies and organisations that look after large areas. For offices and commercial buildings, it suits the frontage, car parks, back alleys and wide common areas where pump-up sprayers are slow.

Key specifications according to SOLO

Source: SOLO manufacturer data. Real-world results depend on nozzle and settings.

Features according to WHD's product information

• Made in Germany with MAHLE parts, a BING carburettor and a Nikasil-coated cylinder.
• ULV output with droplets under 30 microns that saves chemical, according to WHD's product information; actual droplet size depends on the nozzle and setup.
• Long nozzle for distance, wide-angle diffuser, rotatable spray tube.
• UV-resistant translucent tank with a wide filler.
• One-hand lever for throttle, dosing and stop.
• Padded harness with four-point anti-vibration mounts.
• Optional kits in the SOLO range; ask the dealer.

A mistblower, not a thermal fogger

"Fogging machine" is a popular search term, but the SOLO PORT 423 works differently. A thermal fogger uses heat to create smoke. The SOLO PORT 423 is a mistblower that uses air to break liquid into small droplets and blow them out. There is no white smoke to alarm passers-by, and it suits applying water-based disinfectant to surfaces.

Use a properly registered disinfectant

Killing germs is the job of the disinfectant. Choose a registered product suitable for building surfaces and use it per its label, for example Chemgene HLD4H, sold by WHD, and always wash the mud off first.

Engine use around buildings

The SOLO PORT 423 has a petrol engine that produces exhaust and noise, so it belongs outdoors or in well-ventilated open spaces such as sidewalks, open car parks, back alleys and ground-floor halls with doors wide open. For closed offices and small meeting rooms, wipe or use small sprayers, and never start the engine in a closed room.

10 Reasons Offices and Commercial Buildings Should Own a SOLO PORT 423

1. Done in one night. About 12 m of horizontal reach, according to SOLO, makes sidewalks, alleys and car parks quick to cover before opening the next morning.
2. Look after your own surroundings. Frontage and alleys where sewage residue collects get treated immediately.
3. A 12-litre tank for continuous work. Fewer trips back to refill.
4. Airflow reaches into gaps. Up to 1,400 m³/h helps carry disinfectant into drain channels, beside bins and under outdoor shelving.
5. Ready after every downpour. Urban flooding recurs, so owning a machine beats waiting in a queue.
6. Year-round use. Part of the building's hygiene plan in the rainy season or during outbreaks, with a suitable product. See SOLO PORT 423 details
7. German durability. MAHLE and BING parts, according to WHD's product information, for years of repeated use.
8. Fewer people needed. One technician handles outdoor spraying; cleaners focus on wiping touch points inside.
9. Confidence for staff, customers and tenants. You can state that the building washes and disinfects after every flood.
10. Expert advice. WHD advises on disinfectant choice and operation. Call 065-556-6294 or LINE @whd268. Request a quotation

Before and After the Building Owns a SOLO PORT 423

Step by Step: Disinfecting Offices and Commercial Buildings After the Water Drains

Step 1: Check electrics and safety

Cut power to flooded zones and have an electrician check floor sockets, distribution boards and UPS units before use. Make sure no cables are submerged or damaged, and beware of slippery tiles.

Step 2: Inform staff and tenants

Schedule the work after hours or on a holiday and notify staff, tenants and neighbouring shops in advance, since the machine is loud and areas must be closed temporarily.

Step 3: Divide into zones

Ground-floor interior, storerooms and archives, toilets and pantry, frontage, back alley and bin area, car park. Decide which zones allow engine use and which must be wiped by hand.

Step 4: Remove debris and wash off mud

Collect litter, shovel mud and hose floors with clean water and detergent, focusing on skirting, under counters and drain channels at the front. Wear rubber boots and gloves throughout.

Step 5: Deal with absorbent materials

Separate carpet soaked with dirty water, swollen ceiling boards and wet file boxes. Copy or dry important documents quickly, and consider replacing materials that cannot be cleaned.

Step 6: Ventilate and dehumidify

Open doors and windows and use fans and dehumidifiers to dry floors and walls as fast as possible.

Step 7: Prepare product and machine outdoors

Dilute per the label, read the SDS, refuel with the engine off and cool in the open, fill the tank, check caps and hoses, and start the machine outside.

Step 8: Spray outdoor and open areas

Start with the back alley, bin area, frontage and car park. Walk so the wind carries droplets away from you, use the diffuser up close and the long nozzle along corridors, and reduce throttle near shop glass and signs. Keep droplets away from pedestrians, parked cars and neighbouring food shops. An empty ground-floor hall with doors wide open can be treated at low throttle.

Step 9: Wipe indoor touch points

Door handles, lift buttons, stair rails, the reception counter, meeting tables and pantry fittings should be wiped with a suitable product, avoiding direct contact with electronics.

Step 10: Observe re-entry time and record the job

Leave the product for its label contact time, keep everyone out until the re-entry time has passed, ventilate, record date, zone and product, rinse the machine as the manual describes and store it dry.

Safety When Using the SOLO PORT 423 Around Buildings

• Hearing protection. 97 dB(A) at the operator according to SOLO. Always wear earmuffs or earplugs and avoid disturbing neighbours more than necessary.
• Limit operating time. Take regular breaks because of vibration and rotate operators on long jobs.
• Chemical PPE. Chemical-resistant gloves, goggles or face shield, a respirator suited to the label, long sleeves or coveralls, and boots. Follow the label and SDS.
• Safe refuelling. Engine off and cool, outdoors, away from flames, kitchens and smoking areas.
• Full weight. 11.0 kg dry according to SOLO; about 23 kg or more with 12 litres. Fit the harness properly and watch for slippery floors.
• Keep people and animals away. Never spray toward people, animals, food or neighbouring restaurants. Signpost and cordon the zone.
• Re-entry time. Staff and customers return only after the label time.
• Training. Assigned technicians should be trained and read the manufacturer's manual first.
• No engines in closed rooms. Engine exhaust is dangerous; use only where air moves freely.

Buy a Machine for the Building, or Hire a Disinfection Service?

For commercial buildings on main roads that flood often in the rainy season, owning a SOLO PORT 423 lets the building team act as soon as the rain stops and use the machine year-round. Organisations without their own building team, or not ready to buy, can choose WHD's disinfection spraying service as a separate option and contact WHD directly. Owners with several units or branches often share one machine between sites and call in a service for very large jobs.

Frequently Asked Questions About Disinfecting Offices and Commercial Buildings After a Flood

What is the SOLO PORT 423 price, and can a company get a quotation?

Pricing depends on accessories and quantity. Request a quotation from WHD on 065-556-6294 or LINE @whd268, or view the SOLO PORT 423 product page.

Our office ground floor only had a few centimetres of water. Does it need disinfecting?

Wash and dry every time, because urban floodwater often includes drain water. After washing, applying a registered disinfectant reduces residual germs on surfaces.

Can I use the SOLO PORT 423 inside office rooms?

Not in closed rooms. It is an engine with exhaust and noise, best for outdoor and open, ventilated spaces. Wipe and use small sprayers in offices.

Is the SOLO PORT 423 a thermal fogger?

No. It is an air-driven mistblower and does not use heat to make smoke.

Can we spray the sidewalk in front of the building?

Yes, in areas the building is responsible for, at quiet times, with the zone cordoned and droplets kept away from pedestrians and vehicles. For public areas, coordinate with the local authority first.

When should disinfection start after the Nonthaburi flood of 2026 (B.E. 2569)?

After the water drains, the electrics are checked, debris is removed and mud is washed off. The sooner you start, the less chance of mustiness and mould.

Which disinfectant should we use?

A registered disinfectant suitable for your surfaces, diluted per its label, such as Chemgene HLD4H from WHD.

Can staff return to work right after spraying?

Wait for the contact and re-entry times on the label and ventilate first. Spraying in the evening and reopening the next morning works well.

How heavy is it with a full tank?

11.0 kg dry according to SOLO, about 23 kg or more when full. Operators should be fit and trained, and should adjust the harness to their build.

Is there an office disinfection service if we do not want to buy?

Yes. WHD's disinfection spraying service is a separate option. Call 065-556-6294 or LINE @whd268.

Keep Your Building Ready to Reopen After Every Downpour

The 2026 (B.E. 2569) street flooding on Rattanathibet Road is a reminder that buildings on main roads must always be prepared. The German-made SOLO PORT 423 lets your building team wash, then disinfect the surroundings quickly themselves. Ask about specifications and request a quotation today.

View SOLO PORT 423 and Request a Quote

Call 065-556-6294 | LINE @whd268

Related Articles and References

• SOLO Port 423 backpack mistblower against dengue outbreaks, for municipalities and TAOs (Thai)
• Spraying against emerging diseases with the SOLO Port 423, for provincial public health offices (Thai)
• Chemgene HLD4H disinfectant
• WHD disinfection spraying service
• The Bangkok Insight (26 Sep 2026): https://www.thebangkokinsight.com/news/politics-general/general/1700889/
• PRD, DDPM data as of 7 Oct 2026: https://www.prd.go.th/th/content/category/detail/id/33/iid/548715
• CDC flood guidance: https://www.cdc.gov/floods/