The Samut Prakan Floods, 2026 (B.E. 2569)

According to Department of Disaster Prevention and Mitigation (DDPM) data as of 7 October 2026 (B.E. 2569), published by the Government Public Relations Department, Samut Prakan had flooding in six districts: Bang Sao Thong, Phra Pradaeng, Bang Phli, Mueang Samut Prakan, Bang Bo and Phra Samut Chedi. This covered 38 subdistricts, 382 villages and 223,346 households, and water levels were still rising at the time of the report. The household figure had held steady since 4 October 2026 (B.E. 2569) (source: PRD, DDPM data, 7 Oct 2026 / 2569).

Thai PBS and Bangkok Biz News reported that on 27 September 2026 (B.E. 2569) the province declared a disaster zone covering every subdistrict in all six districts, after heavy rain combined with high tides from 23 September 2026 (B.E. 2569). On 1 October 2026 (B.E. 2569) the governor warned that water in Bang Phli, Bang Bo and Bang Sao Thong would not recede within 7 to 10 days (sources: Thai PBS and Bangkok Biz News, 2026 / 2569).

Nationally, DDPM data at 06:00 on 7 October 2026 (B.E. 2569) showed flooding in 27 provinces plus Bangkok, covering 123 districts, 984 subdistricts and 1,154,875 households, with more than 3.1 million people affected.

Samut Prakan is dense with condominiums, from Bang Phli and the Bang Na-Trat corridor to Samrong and Pak Nam. Many buildings have basement or low-lying car parks. When heavy rain meets a high tide and drains cannot cope, water runs down ramps into car park levels, pump rooms and refuse rooms.

Example Case: A Condo with a Submerged Basement Car Park

The following is an illustrative example based on situations common in condominiums after floods. It does not describe any specific building or real person.

Wit (not his real name) is the building engineer of a thirty-storey condo in Bang Phli. The building has several hundred units, two basement car park levels, a large lobby, a central refuse room, a pump room and electrical plant on the lower floors.

The night of the heaviest rain coincided with a high tide. Water from the street flowed over the ramp barrier and poured into the car park. The technical team had to cut power to some areas and pump hard. Several residents' cars were submerged, and the basement refuse room flooded, scattering rubbish bags. Days later, when the water was finally pumped out, what remained was a film of mud over every surface, water lines on walls and columns, the stench of rubbish and wastewater, and humidity trapped in an enclosed space.

Residents began asking in the building LINE group: "When can we park again?" "Are there germs in the car park?" "Why does the lobby smell musty?" Housekeepers mopped and used a hand-pump sprayer, but two car park levels meant several thousand square metres full of columns, beams, pipes and drains. Mopping bay by bay took forever, and hand-pump droplets never reached the beams or ceiling.

Wit proposed to the juristic person committee that a building in a repeat flood zone should keep an engine-powered backpack mistblower, with a strict operating procedure on ventilation, so the building team could disinfect large areas itself rather than wait for contractors.

Germs and Risks in a Flooded Underground Car Park

An underground car park is enclosed, sunless and poorly ventilated. Once flooded, it holds germs far better than open ground:

• Bacteria such as E. coli and Salmonella from wastewater backing up through drains and treatment tanks, which cause diarrhoea and food poisoning, and Leptospira, the cause of leptospirosis, carried in the urine of rats that live in refuse rooms, ducts and dark corners of basements.
• Viruses such as norovirus and rotavirus, spread via shared surfaces. Respiratory viruses such as RSV and influenza spread easily in shared enclosed spaces like lifts and lobbies when many residents stay indoors because getting out is difficult.
• Moulds that grow on walls, columns, ceilings and residents' storage rooms when damp lasts more than 24 to 48 hours. Ventilation fans can carry spores to other parts of the building, causing musty smells and triggering allergies.

High-risk touch points in a condo include lift buttons, stair rails, fire doors, car park barriers, parcel lockers, the refuse room and the walkway from the car park to the lobby. Older residents, young children and people with chronic illness need extra protection.

Anyone who waded through car park water and then develops high fever, headache, calf pain, red eyes or diarrhoea should see a doctor and mention flood exposure. Disinfecting common areas reduces environmental risk; it does not replace treatment.

Problems Condominium Juristic Persons Face After the Water Drops

Large, complex spaces

Multi-level car parks cover thousands of square metres, with many columns, beams, pipes, drains and bays. Wiping or small-tank spraying one spot at a time takes days.

Residents need the car park every day

It is the main entrance for many residents. Each day it stays closed adds inconvenience and frustration.

The building team is stretched

Technicians must check electrics, pumps, lifts and fire systems, while housekeepers shovel mud and haul rubbish. Sparing someone to pump a hand sprayer all day is difficult.

Smells and damp rise into the building

If the basement is not cleaned and dried quickly, musty air and mould spores can rise through lift shafts and stairwells and affect the whole building.

Accountability to co-owners

A condominium juristic person spends co-owners' common fees and must show a systematic, transparent plan that protects everyone.

Unit values and reputation

Buildings that recover quickly without lingering smells or mould protect unit values and rental appeal. Chronic post-flood problems can easily become an online story.

Why Mops and Hand Pumps Cannot Handle a Whole Car Park Level

• Mops and cloths work for small areas but cannot reach columns, high walls, beams and ceilings, where water lines and mould appear.
• Hand-pump sprayers have low pressure, short reach and large droplets, and operators tire quickly. They do not suit thousands of square metres.
• Pressure washers remove grime well but are not disinfectant applicators, and they send large volumes of water into drains and sumps.
• Small battery sprayers have small tanks, need frequent charging and lack the airflow to lift droplets to high beams and ceilings.
• Relying on ventilation fans alone helps drying but does not disinfect, and once mould has started, fans may even spread spores.

The job needs a machine one person can carry, with airflow that lifts droplets high and pushes them into gaps, a tank big enough for large areas, independence from partly repaired electrics, and a safety procedure designed for underground spaces.

SOLO PORT 423: The Answer for Condominium Common Area Disinfection

The SOLO PORT 423 is an engine-powered backpack mistblower made by SOLO Kleinmotoren GmbH in Germany. A high-volume fan breaks liquid into fine droplets and sends them out in a long stream to coat surfaces over a wide area. WHD sells the unit to government agencies and large organisations, including condominiums with extensive common property.

Key specifications (according to SOLO manufacturer data)

• Single-cylinder two-stroke engine, 72.3 cm³ displacement
• Power 3.0 kW (4.1 HP)
• 12-litre spray-liquid tank
• Maximum airflow 1,400 m³/h
• Horizontal reach about 12 m
• Dry weight about 11.0 kg
• Sound pressure at the operator 97 dB(A)

Features according to WHD product information

According to WHD's product information, the unit produces fine ULV-type droplets under 30 microns, helping save chemical. It uses MAHLE and BING parts and a Nikasil-coated cylinder, with a UV-resistant translucent tank and wide filler, a rotatable spray tube, a long nozzle and a wide-angle diffuser, a one-hand lever for throttle, dosing and stop, a padded harness and four-point anti-vibration mounts. Actual droplet size depends on nozzle and settings. For other optional kits in the SOLO range, ask the dealer.

Not a thermal fogger

People often call every sprayer a "fogging machine", but the SOLO PORT 423 does not heat liquid into smoke. It uses air to break the liquid into droplets, which suits water-based disinfectants that should settle on surfaces, and it does not fill the building with thick smoke.

The disinfectant works; the machine distributes

Results depend on the product. Use a registered, non-flammable disinfectant, mixed and applied according to its label, such as Chemgene HLD4H from WHD, and always remove mud first, since dirt reduces activity.

Golden Rules for Running an Engine in an Underground Car Park

This is the most important section for condominiums. The SOLO PORT 423 runs on a two-stroke petrol engine, and its exhaust contains carbon monoxide. Underground use must be tightly controlled.

• Run the car park ventilation system at full capacity before and during spraying. If the extract fans were damaged by the flood, do not run the engine underground; repair them first or use another method.
• Never run the engine in a closed room such as a shut refuse room, store room or plant room. Keep doors open and air moving at all times.
• Use a carbon monoxide detector if the building has one, and always have a second person present.
• Stop at once and move to fresh air if the operator or helper has a headache, dizziness, nausea or unusual tiredness.
• Coordinate fire alarm arrangements with the building engineer. Mist and exhaust can set off some detector types. Plan this under the building's safety procedures, and never disable fire protection without a responsible person in charge.
• Never spray onto electrical panels, sockets or equipment, and keep out of electrical rooms; electricians should handle those to their own standards.
• Refuel outside the building, in the open, with the engine off and cool. Never refuel in the basement.
• Work zone by zone, starting nearest the fresh-air intake, and step outside for fresh air at regular intervals.

10 Reasons Condominiums Should Own a SOLO PORT 423

1. About 12 m horizontal reach according to SOLO manufacturer data. Walk the driving aisle and the mist covers bays on both sides.
2. 1,400 m³/h airflow lifts droplets to beams, columns and ceilings that mops cannot reach.
3. A 12-litre tank covers a lot of ground before you must go out to refill.
4. No socket needed, so work goes on while electrics are still partly under repair.
5. Easy to carry down ramps, between columns, into refuse rooms and lift lobbies.
6. Fine droplets, according to WHD product information, use less product than pouring and leave floors less wet, so residents can return sooner.
7. German-quality parts from MAHLE and BING for repeated use every rainy season.
8. Year-round use for post-flood disinfection, refuse room hygiene and insect control with suitably labelled products.
9. Your building team starts on its own, without queueing for contractors while the whole province needs help.
10. Confidence for co-owners. A juristic person with equipment and a plan can answer residents immediately. See the SOLO PORT 423 product page.

Before and After the Building Owns a SOLO PORT 423

This comparison reflects typical work patterns. Actual speed depends on building size, obstacles, ventilation condition, operator skill and the label application rate.

Step by Step: Disinfecting an Underground Car Park and Common Areas After the Flood

Step 1: Check building safety first

Have the building engineer inspect electrics, pumps, lifts and extract fans. Keep out of areas with standing water that may be live. Confirm car park ventilation is working.

Step 2: Notify residents and move cars

Announce a zone-by-zone timetable. Ask residents to move cars out of the zone or close windows fully, and to avoid walking through during set times.

Step 3: Remove rubbish and mud

Collect scattered rubbish bags, clean the refuse room, shovel mud, flush drains, then wash floors, columns and walls with clean water and detergent.

Step 4: Discard porous materials

Remove cartons, carpets and soaked items from common storage. For residents' belongings, inform the owners first.

Step 5: Ventilate and dry

Run extract fans at full power with extra fans if needed. Faster drying means less mould.

Step 6: Prepare product and machine outside

Choose a registered, non-flammable disinfectant such as Chemgene HLD4H and mix at the label rate. Read the SDS. Refuel outside in the open with the engine off and cool, and start the machine in an open area before going down.

Step 7: Spray zone by zone, top to bottom

Start with beams and ceiling, then columns, walls and floor. Work from the innermost zone back toward the fresh-air intake, never walking back into fresh mist. Step outside for fresh air on a schedule, with a helper watching at all times.

Step 8: Treat shared touch points by wiping

For lift buttons, handrails, door handles and parcel lockers, wipe with a suitable product instead of spraying electrical equipment directly.

Step 9: Respect contact and re-entry times

Let the product work for the labelled time, keep ventilation running, and reopen zones only after the re-entry time has passed.

Step 10: Clean, log and follow up

Rinse tank and nozzle per the manual. Record zone, date, product, mix rate and operator. Check for musty smells and mould over the next one to two weeks, then update the building's flood plan for next year.

General Safety When Using the SOLO PORT 423

• Hearing protection. Sound pressure at the operator is 97 dB(A) according to SOLO manufacturer data, and it echoes more in enclosed spaces. Operator and helper must wear earmuffs or earplugs.
• Vibration. Even with the four-point anti-vibration mounts WHD describes, limit continuous spraying, rotate operators and take breaks.
• Chemical PPE. Chemical-resistant gloves, goggles or face shield, a respirator suited to the label, long sleeves or coveralls and boots, per the SDS.
• Refuelling. Engine off and cool, outdoors in the open, away from flames. Store fuel according to building safety rules.
• Weight. About 11 kg dry and roughly 23 kg or more with a full 12-litre tank. Watch for slippery floors and steep ramps.
• Keep people and pets out of the spray zone, and do not spray toward cars with open windows.
• Re-entry times on the label must be followed strictly.
• Training. Operators must learn starting, dose control, stopping, ventilation rules and the warning signs of exhaust exposure before real use.

Buy a Unit for the Building or Hire a Disinfection Service?

Condominiums in repeat flood zones with large basement car parks and in-house technicians benefit from owning a SOLO PORT 423 as common property: work begins immediately, the machine lasts for years, and it serves routine refuse room and open-area hygiene.

Buildings without a ready team, or that prefer not to buy, can use WHD's disinfection service as a separate option and contact WHD directly.

Frequently Asked Questions

What is the SOLO PORT 423 price, and can a condominium juristic person get a quotation?

Yes. Price depends on configuration and quantity. Contact WHD on 065-556-6294 or LINE @whd268, or see the SOLO PORT 423 product page.

Does a flooded underground car park need disinfecting?

It should be, because floodwater usually carries wastewater and rubbish. Remove mud and clean first, then apply a registered disinfectant according to its label.

Is it safe to use an engine-powered sprayer in an underground car park?

Only with the car park ventilation running at full capacity, a helper present, and an immediate stop if anyone gets a headache or dizziness. Never use it in closed rooms or while extract fans are out of action.

Is the SOLO PORT 423 a fogging machine?

No. It is an air-driven mistblower and does not heat liquid into smoke.

Will spraying set off the fire alarm?

It can with some detector types, so plan with the building engineer beforehand under the building's safety procedures.

Can we spray disinfectant on residents' cars?

No. Ask residents to move cars out of the zone or close windows fully. Flood-damaged cars should be cleaned by a garage or vehicle specialist.

How soon after the Samut Prakan 2026 (B.E. 2569) floods can disinfection start?

As soon as water is pumped out, mud removed and the area washed. Avoid waiting longer than 24 to 48 hours, as mould begins to grow.

How heavy is the machine with a full tank?

About 11.0 kg dry according to SOLO manufacturer data, and roughly 23 kg or more with 12 litres of liquid.

What protective equipment is required?

Hearing protection, chemical-resistant gloves, goggles, a suitable respirator, long sleeves or coveralls and boots, per the label and SDS.

Is there a service if the building does not want to buy?

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

Help Your Building Recover After Floods with the SOLO PORT 423

A German backpack mistblower with a 12-litre tank, 1,400 m³/h airflow and about 12 m reach, according to SOLO manufacturer data, so your building team can disinfect car parks and common areas itself, safely.

For a quotation or advice, call 065-556-6294 | LINE @whd268

Related Reading and References

• SOLO PORT 423 backpack mistblower for dengue control by municipalities and TAOs (Thai)
• SOLO PORT 423 against emerging disease for provincial public health offices (Thai)
• Chemgene HLD4H disinfectant
• WHD disinfection service
• PRD: flood situation, DDPM data, 7 Oct 2026 / 2569
• Thai PBS: Samut Prakan floods, 2026 / 2569
• Bangkok Biz News: Samut Prakan flood situation, 2026 / 2569