What happened at Ramkhamhaeng University

According to a report by Thai PBS, flooding at Ramkhamhaeng University lasted from 25 September to 1 October 2026, roughly six days. In some places the water rose to almost two metres, which is extremely deep for an area made up of classrooms and offices. The report said that more than half of the university's 65 buildings were affected, and an initial damage estimate exceeded 200 million baht. It was described as the worst flooding the campus had seen in around four decades.

The buildings named in the report were very different from one another: the Computer Institute, the Faculty of Education, the Central Library, the demonstration school, the sports centre and the medical service unit. Some are packed with electronics, some with books and paper, one is where young children learn every day, and one is a health service point that needs a higher standard of hygiene than an ordinary room.

Thai PBS also reported a decision that stands out: the university chose not to pump flood water out into the surrounding communities. In practical terms that means water had to drain away through the normal system, and areas inside the campus may have stayed flooded longer than if pumps had been used aggressively. From a hygiene perspective, floors, furniture and walls were in contact with water for several days, which is exactly the kind of condition that favours mould growth and the build-up of grime.

On the academic side, the report said the university planned to resume classes on 5 October 2026 and to keep its final exams on the original schedule, from 14 to 28 October. That leaves a very short window between the water going down and thousands of students sitting together in exam rooms. Cleaning and disinfection therefore have to be organised and fast.

Note: the figures above come from the Thai PBS report as of its publication date. Field conditions and damage estimates can change as the university completes its own assessment, so please also follow the university's official announcements.

A short timeline for facility managers

• 25 Sept 2026: water begins to flood the campus, according to Thai PBS.
• About 6 days: the period the water stayed, nearly 2 metres deep in some spots.
• 1 Oct 2026: end of the reported flood period.
• 5 Oct 2026: classes scheduled to resume.
• 14 to 28 Oct 2026: final exams on the original timetable.

The recovery window is only a matter of days, so the order of work matters more than trying to do everything at once.

Example case: Nan's ground-floor dorm room near campus

This is an illustrative scenario built from problems commonly seen after floods. Nan is not a real person from the news report.

Nan is a third-year student renting a ground-floor room in a dormitory in the Ramkhamhaeng area. When the water rose she moved in with a friend. Coming back after the water receded, the first thing she noticed was the smell: a damp, musty odour mixed with a drain smell that hit her as soon as the door opened. The wooden bed legs had a waterline above knee height, the shoe cabinet had swollen, and small black spots were appearing along the bottom of the walls.

Nan swept out the mud, mopped with an ordinary floor cleaner and left a fan running. Two days later the smell was still there, the black spots had crept higher, and she started sneezing and waking up congested at night, just days before classes and exam revision began.

Her situation is not limited to dorm rooms. It mirrors what happens across thousands of square metres of classrooms, library space and offices. Washing until something looks clean does not mean it is free of germs, and letting surfaces dry without disinfecting often gives mould and bacteria a chance to come back sooner than expected. The right order is to remove all the mud, dry the surfaces, and finish with an effective disinfectant at the dilution shown on the label.

Which germs follow a flood onto a university campus

Urban flood water is not clean rain water. It runs across roads, through drains and manholes, and over ground that may contain sewage. The World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) both warn that flood water can be contaminated with sewage and chemicals and can lead to infectious disease. Thailand's Department of Disease Control issues warnings about flood-related illnesses every rainy season. On a campus where large numbers of people come and go every day, the following groups deserve special attention.

1. Sewage bacteria such as E. coli and Salmonella

These bacteria usually come from faeces and wastewater. Left on floors, desks, handrails or canteen counters, they can transfer to hands and then to the mouth. Common symptoms are diarrhoea, stomach cramps, nausea, vomiting and fever. With many canteens, food stalls and drinking-water points on a campus, disinfecting food preparation areas and dining tables is a top priority.

2. Leptospirosis

Leptospira bacteria live in the urine of animals such as rats and can survive in standing water and wet soil. People who wade through water or mud to carry things, wash buildings or clear debris can be exposed through cuts or skin that has been soaked for a long time. Typical signs are a sudden high fever, muscle pain especially in the calves, and red eyes. Anyone who has waded through flood water and develops these symptoms should see a doctor right away and mention the exposure. Surface disinfection reduces repeated contact, but the most direct protection is boots, gloves and good wound care.

3. Viruses that spread easily where people gather

Norovirus and rotavirus cause diarrhoea and vomiting and can persist on surfaces. Respiratory viruses such as influenza and RSV spread through droplets and through hands touching shared surfaces: door handles, lift buttons, lecture desks, keyboards and computer mice. Hand, foot and mouth disease is common in young children, which makes it particularly relevant to the demonstration school, where children share classrooms and toys.

4. Mould and musty odours

Buildings that sit in water for days are ideal for mould: gypsum walls, ceiling boards that absorb moisture, carpets, curtains, upholstered chairs and, above all, books and paper in a library. WHO and CDC advise cleaning and drying as quickly as possible, generally within 24 to 48 hours, to limit mould growth. When water stays for several days, mould may already be starting before anyone can get back inside. Mould spores can trigger allergies, asthma and irritation of the airways.

Different buildings, different risks

Knowing which kinds of buildings were flooded makes it possible to prioritise disinfection by risk. What follows is a reasoned analysis based on the building types named in the news report, not on any measurements taken inside them.

The demonstration school should come first. Its users are children whose immune systems are still developing, who touch everything and often put their hands in their mouths. Desks, chairs, toys, learning materials, toilets, sinks and eating areas all need thorough washing and disinfection. Fabric toys or absorbent materials soaked in dirty water for days are usually better thrown away.

The medical service unit needs clinic-level hygiene. People who visit may already be unwell. Examination couches, waiting-room chairs, counters and any medical equipment that touched water should be assessed according to the equipment manufacturer's guidance. After that, general surfaces should be disinfected with a product suitable for healthcare settings.

The Central Library faces a double problem: large numbers of wet books and documents, and a room structure that has absorbed moisture. Rescuing books is specialist work and should involve conservation experts. Metal shelving, reading tables, floors and washable walls can be disinfected after washing and drying.

The Computer Institute is full of electrical equipment. No liquid should ever be sprayed onto equipment that is still plugged in or has not been checked by an electrician. The facilities team should cut the power and inspect first. Then desks, chairs and floors can be cleaned, and the outer surfaces of devices wiped with a well-wrung cloth following the manufacturer's advice.

The Faculty of Education and general teaching buildings have large lecture rooms, rows of desks and busy corridors. Shared touch points such as door handles, handrails, lift buttons and light switches are the main targets.

The sports centre has rubber flooring, mats, exercise equipment, locker rooms and showers, spaces that are naturally damp even in normal times. After a flood they are at even higher risk of mould and skin-transmitted germs, so a disinfectant that does not corrode rubber and plastic is important.

Who is most at risk when the campus reopens

• Demonstration school pupils: at risk of diarrhoeal illness and hand, foot and mouth disease because of how they touch surfaces and their mouths.
• Students during exams: seated close together, short on sleep and under stress, which can lower immunity and make it easier for influenza and RSV to spread.
• Cleaning and maintenance staff: in direct contact with mud and standing water, at risk of leptospirosis, infected wounds and inhaling mould spores.
• Older staff and people with chronic conditions: such as diabetes, lung disease or weakened immunity, for whom infections can be more serious.
• Patients using the medical service unit: who may already be ill or frail.
• People with allergies and asthma: sensitive to mould and musty air in closed rooms.

Knowing the high-risk groups helps set the order of work: start with the demonstration school, the medical unit, toilets and canteens, then move on to lecture halls and exam rooms.

Why soap, detergent or bleach alone falls short

Credit where it is due: soap, detergent and clean water are an essential step. They lift mud and dirt off surfaces. Without that first wash, no disinfectant can work properly, because organic soil reduces its effectiveness. But washing alone has clear limits.

First, soap is not designed to disinfect surfaces comprehensively. It helps rinse germs away with the dirt, but when contaminated rinse water is pushed around with the same mop, germs can simply be moved from one room to the next.

Second, bleach has drawbacks in corrosion and smell. Chlorine bleach is recommended by many health agencies for emergencies and works when mixed correctly. In practice, though, it can corrode some metals, fade or weaken fabrics and other materials, gives off a sharp smell that irritates the airways in closed rooms, and is dangerous if mixed with acidic or ammonia-based toilet cleaners, which can release toxic gas. In buildings full of metal shelving, sports equipment and furniture, those drawbacks become very visible.

Third, there is no lasting protection. Ordinary soap and bleach work while wet. Once dry, the surface is just an ordinary surface again, ready for new germs to land. When thousands of people return to a building, a product that states residual surface protection is a real advantage.

The solution: CHEMGENE HLD4H, a medical-grade disinfectant for post-flood recovery

Once the mud is gone and surfaces are dry, the step that completes the job is disinfection with a product that has clear supporting information. CHEMGENE HLD4H is a medical-grade, high-level disinfectant made in England. According to the product information, its key points relevant to a university are:

• Listed activity against bacteria, fungi and mould, mycobacteria, Salmonella and many viruses, including influenza H1N1, RSV, norovirus, hand, foot and mouth disease virus and SARS-CoV-2.
• The product page states it kills within 1 minute and shows 99.85% efficacy against COVID-19.
• Residual surface protection of up to 14 days is stated.
• Several dilution rates: 1:30, 1:50, 1:60, 1:100 and up to 1:200 depending on the task.
• Biodegradable, and non-corrosive to stainless steel, aluminium, rubber, plastic and fibreglass.
• The product page states it is safe for people, pets and medical equipment when used as directed.
• Listed tests and approvals include Mahidol University, NHS England, ISO 9001:2015, ISO 13485, SGS, Intertek, CE, and EN 13727, EN 14348, EN 13624 and EN 14476.
• Used in hospitals, clinics, laboratories, schools, offices, airports, homes, and elderly and child care settings.

How to use Chemgene HLD4H after the water recedes

1. Safety first. Facilities staff should cut and inspect electrical systems before anyone enters. Everyone wears boots, rubber gloves and a mask. People with open wounds should cover them fully or avoid wading.
2. Remove mud and damaged items. Take out absorbent materials that cannot be saved, such as carpets, sagging gypsum ceiling boards, fabric seats and soft toys.
3. Wash with clean water and detergent. Scrub mud from floors, lower walls, desk legs and shelves. Rinse until the water runs clear. Do not skip this step, because disinfectants work best on clean surfaces.
4. Ventilate and dry. Open windows and use fans or dehumidifiers where appropriate.
5. Dilute Chemgene HLD4H as shown on the label. The product information lists rates from 1:30 to 1:200. Choose the rate that matches the surface and risk level according to the label or supplier advice. Use clean, clearly labelled containers and never mix with other chemicals.
6. Spray or wipe all surfaces evenly and leave the solution in contact for the time stated on the label. Focus on shared touch points: handles, handrails, lift buttons, desks, taps and toilet doors.
7. Wipe, do not spray, electrical equipment. Use a microfibre cloth that has been dampened and wrung out, only on external surfaces, only after an electrician's check, and following the device maker's advice.
8. Repeat in rounds, especially on shared touch points during busy exam periods.

The rule to remember: wash off the mud, dry, then disinfect per label. A disinfectant does not replace cleaning. It is the finishing step that makes the cleaning count.

10 reasons Chemgene HLD4H suits a university's flood recovery

1. It is medical grade. Classed as a high-level disinfectant in the product information, it suits demanding areas like the medical service unit and the demonstration school.
2. Broad coverage. Bacteria, fungi and the viruses that spread in crowded spaces are all on the list.
3. Fast stated action. The product page states it works within 1 minute, which keeps cleaning teams moving.
4. Residual protection of up to 14 days, as stated, which suits the period when classes and exams bring everyone back at once.
5. Non-corrosive to key materials, including stainless steel, aluminium, rubber, plastic and fibreglass, common in library shelving, handrails and sports equipment.
6. No harsh chlorine smell, so lecture and exam rooms do not reek of chemicals that break concentration.
7. Flexible dilution. One concentrate covers many jobs, which helps budget planning for large areas.
8. Biodegradable, in keeping with a university that has shown concern for its neighbouring communities.
9. A list of tests and certifications from several institutions, including Mahidol University, NHS England, SGS, Intertek and EN standards, useful for procurement decisions.
10. Works on campus and off campus. Chemgene HLD4H can be used in large buildings and in the dorms and rented rooms around the university.

Before and after: one classroom

Zone-by-zone checklist for Ramkhamhaeng after the flood

Demonstration school

• Throw away fabric toys and absorbent items soaked in dirty water.
• Wash desks, chairs and plastic toys with detergent, dry, then disinfect per label.
• Finish children's toilets, sinks and eating areas before pupils return.
• Provide enough handwashing points with soap.

Medical service unit

• Assess any medical equipment that touched water according to the manufacturer.
• Disinfect couches, waiting chairs, counters and toilets after washing.
• Clearly separate clean areas from areas still being restored.

Central Library

• Consult document conservation specialists about wet books.
• Wash and disinfect metal shelving, reading tables and floors.
• Keep controlling humidity to stop mould returning.

Computer Institute

• Cut the power and have an electrician inspect first. Never spray onto electrical equipment.
• Wipe keyboards, mice and outer casings with a wrung-out cloth per the maker's advice.
• Disinfect desks, chairs and lab floors.

Sports centre and locker rooms

• Wash rubber floors, mats and equipment, then disinfect per label.
• Give priority to damp showers and locker rooms.

Lecture halls and exam rooms

• Disinfect every lecture desk before classes resume.
• Schedule daytime rounds for shared touch points during exams from 14 to 28 October.
• Ventilate before and after each exam session.

For students and the community around Ramkhamhaeng

The university does not stand alone. Around it are dormitories, rented rooms, restaurants, print shops and many homes. The university's choice not to pump water out into its neighbours, as reported by Thai PBS, shows that everyone shares the same water system. Once the water is gone, the campus and the community should recover together, because germs do not stop at the fence.

Students living in dorms or rented rooms should follow the same order: wash off the mud, dry, throw away absorbent items that cannot be saved, then disinfect floors, bed legs, study desks, bathrooms and small kitchen corners with a disinfectant diluted per label. Look after yourself during exams, too: sleep enough, drink clean water, wash your hands before eating, and if you develop a high fever, calf pain, severe diarrhoea or difficulty breathing, see a doctor right away.

Frequently asked questions

Can Chemgene HLD4H replace washing off the mud?
No. Always remove mud and dirt first, then dry, and only then disinfect at the label dilution and contact time. Disinfectants work best on clean surfaces.

Can it be used in the demonstration school with young children?
According to the product information it is used in child care settings, and the product page says it is safe for people when used as directed. Apply it when children are not in the room, allow it to dry for the stated time, and always store it out of children's reach.

Can I spray it on computers?
Do not spray any liquid onto electrical equipment. Cut the power and have it inspected first, then wipe only the external surfaces with a wrung-out cloth following the device maker's guidance.

Which dilution should I use?
The product information lists 1:30, 1:50, 1:60, 1:100 and up to 1:200. Choose according to the surface type and risk level, with the label or supplier advice as your guide.

I waded through flood water and now have a fever and calf pain. What should I do?
See a doctor immediately and say you were in flood water, as this can be a sign of leptospirosis. Disinfectants are for surfaces, not for treating illness.

If it floods again, do I need to start over?
Yes. If water returns or surfaces are covered in mud again, wash and disinfect again. Stated residual protection applies to surfaces that stay clean, not to surfaces submerged in dirty water a second time.

Get classrooms ready for students, safely

Interested in CHEMGENE HLD4H for teaching buildings, dormitories, shops or your home? Ask about the right dilution for your space and how much you need.

See Chemgene HLD4H details

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

Related links and references

• CHEMGENE HLD4H medical-grade disinfectant
• Ozone disinfection service after floods
• Thai PBS report on the Ramkhamhaeng University flood: https://www.thaipbs.or.th/news/content/559039
• World Health Organization fact sheets: https://www.who.int/news-room/fact-sheets
• CDC floods and clean-up: https://www.cdc.gov/floods/
• Thailand Department of Disease Control: https://ddc.moph.go.th/

Product information is taken from the supplier's product page. Disinfectants help reduce the risk of infection from surfaces. They do not prevent flooding and are not medical treatment. Anyone who is ill should see a doctor. Always follow the label.