Post-Holiday Respiratory Virus Outbreak Stopped in a Silom Office with Airofog U260 ULV

The First Day Back from Songkran

It was the Tuesday after Songkran, and Nuch, the HR manager of a mid-size consulting firm on Silom Road, walked onto the 14th-floor office expecting a slow morning. Instead she found 14 empty desks. The first message had already arrived in the company Line group: "Fever 39°C, dry cough, sore throat. ATK positive."

Within three hours, seven more colleagues replied with the same symptoms — and by lunch, the medical clinic on the ground floor was reporting a mix of Influenza A, Influenza B, COVID-19, and RSV. None of them were related to Songkran travel — every one of these 14 people had visited family separately, in different provinces. The common thread was the office.

The firm employed 96 people. A major project was due Friday for a Fortune-500 client. If infections doubled by week's end, the project would slip — and Nuch knew that meant either a discount, a churned client, or both.

Why Offices Are the Number-One Outbreak Site

Respiratory viruses — Influenza A/B, RSV, SARS-CoV-2, Rhinovirus — spread through fine droplets from coughing, sneezing, and just talking. These droplets stay airborne for 30 minutes to several hours inside an air-conditioned, sealed office.

Thai offices typically have low fresh-air exchange rates. Workstations are 80–100 cm apart. Keyboards, mice, door handles, water dispensers, lift buttons, copier panels — these high-touch surfaces hold infectious virus for 1–3 days at typical indoor humidity.

The Thai DDC recommends "air + surface disinfection" inside any office that records two or more cases within seven days, with priority on meeting rooms, kitchens, and high-touch points.

Hidden Costs Executives Forget

Wasted payroll. 14 staff × THB 1,200/day average × 7 sick days = THB 117,600 hits P&L immediately.

Project slip. Late delivery on a Fortune-500 contract = service credits of THB 50,000–200,000, plus possible churn.

Attrition. Staff who catch the virus at work begin polishing their CVs. Each replacement costs THB 80,000–150,000 in recruiting.

Reputation. "They don't take care of their people" travels fast through the local HR network. Senior-hire pipeline dries up.

Legal exposure. In severe cases, employees may demand medical compensation under labour law.

Why the Usual Office Fixes Fall Short

Alcohol spray bottles. Hit only the surfaces you can see. Nothing reaches under keyboards, inside cabinets, or into the air.

Hiring an outside disinfection crew. THB 8,000–25,000 per visit, 2–3 days lead time, requires a full-day shutdown. You lose a billing day on top of the fee.

HEPA air purifiers. Good for dust and odour. Inadequate at killing live virus on surfaces, and need 6–8 hours of runtime to achieve a 90% in-air reduction.

Shutting off central AC. Makes the office uncomfortable, doesn't break the transmission chain, and irritates everyone.

What HR needs is a machine the admin team can use every Monday morning before staff arrive — covers both air and surfaces, takes under an hour, and lets staff walk in 10–15 minutes later.

Meet Airofog U260 — the Tool Silom Chose

Nuch called World Health Disinfection at midday. By 4 p.m. the same day, an Airofog U260 and 5 L of Chemgene HLD4H disinfectant were on the 14th floor.

Why U260 fits an office: 4.5 kg shoulder-carry, runs on standard 220 V power, 5–50 micron droplets that stay airborne for 30–60 minutes, 75 dB noise floor (no disturbance to neighbouring tenants), and uses only ~200 ml of solution per 500 m² of office.

That evening "P'Tu", the office facilities lead, fogged the entire 900 m² floor — three meeting rooms, kitchen, and 96 workstations — in 30 minutes. By the next morning the office was clear, dry, and odour-free. Staff returning to their desks messaged: "the air feels light".

How ULV Disinfection Actually Works in a Closed Office

ULV uses very little liquid but breaks it into micron-scale droplets. The mist stays suspended, contacting any virus particles in the air and depositing a thin film on every surface, including the ones a spray bottle can never reach.

With Chemgene HLD4H — a quaternary-ammonium plus biguanide formulation certified to EN 14476 — Influenza A/B, Coronavirus, RSV, and Norovirus are inactivated within 1–5 minutes of contact. The U260 also works with diluted sodium hypochlorite, generic quats, or hospital-grade hydrogen peroxide.

10 Reasons Offices, Condos and Hotels Choose Airofog U260

1. Air and surfaces in one pass — no separate purifier needed.

2. 900–1,500 m² in 30–45 minutes — done before staff arrive.

3. Re-entry in 10–15 minutes after fogging stops, per chemical guidance.

4. Fast ROI — replaces THB 288,000/year of outside crew billing in 4–6 months.

5. Electronics-safe — micron mist dries fast, no damage to keyboards or screens.

6. Mission flexibility — swap tanks for mosquito or pest control by mid-afternoon.

7. Variable droplet size — fine for meeting rooms, coarse for corridors.

8. Quiet — 75 dB, no complaints from the next office.

9. 1-year factory warranty with Thai spare-parts stock.

10. On-site training included. Call 065-556-6294 or LINE @whd268.

Before vs After — the Silom Office

Before: 14 staff sick, an anxious leadership team, an emergency WFH plan, a Friday project at risk, and an awkward call with the Fortune-500 client.

After (10 days): Zero new infections. Project delivered on time. Staff posting "the air feels lighter" on the company Line group. Facilities now fogs every Monday before 8 a.m. and ahead of every all-hands meeting.

Nuch, HR Manager — in Her Own Words

"We used to pay an outside crew THB 12,000 per visit, twice a month. The U260 paid for itself in five months. But the real win is being able to fog every Monday morning before people arrive, and before every big client meeting. Sick days are down 70% versus last year."

— Nuch, HR Manager, consulting firm in Silom

FAQ

Q: Can we run AC during fogging?
A: Switch off AC, close doors and windows for 30 minutes, then ventilate for 15 minutes before staff enter.

Q: Does it actually kill COVID?
A: With an EN 14476-certified disinfectant like Chemgene HLD4H, yes — inactivation in 1–5 minutes of contact.

Q: How often?
A: Weekly or bi-weekly is typical. Plus whenever a case is reported.

Q: Price?
A: Product page or call 065-556-6294.

Take Control of Office Air Quality Today

See specs and price: click here

Call now: 065-556-6294 | LINE: @whd268

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• CDC — Seasonal Influenza