Case study: epoxy floor odor in a food factory

Frozen Food Plant's New Epoxy Floor Fails a Japanese Audit, Halting Packing 6 Days Over a Chemical Smell on Packaging

When epoxy floor odor in factories seeps into cartons, bags and customer confidence, "just wait it out" becomes a very expensive plan. Here is what went wrong, and how ozone paint odor removal with measurable results helped put it right.

Six Silent Days in the Packing Room: The Thara Frozen Story

This story is a composite based on situations we commonly see; names and places are fictional.

Most managers treat epoxy floor odor in factories as a minor nuisance that fades on its own. For Worachet, plant manager at "Thara Frozen", a mid-sized frozen food packing plant in Samut Sakhon, just outside Bangkok, that smell shut down his packing line for six full days and nearly cost the company its biggest customer.

Thara Frozen employs around 180 people and ships frozen gyoza and battered shrimp to Japan, roughly four containers a month. The heart of the operation is a 620-square-metre packing room with a 4.5-metre ceiling, held at about 12°C. It is a sealed space where almost all of the air is recirculated through the HVAC system.

A holiday shutdown that seemed like perfect timing

The old floor had started to crack and pit. Arunee, the Quality Assurance manager, had been warning for months that the damaged surface could harbour bacteria. So during the five-day Songkran holiday in April, the plant hired a contractor to pour a 3-millimetre self-levelling epoxy floor, finished with a protective topcoat.

The contractor finished on schedule on the night of day four. "You can walk on it now," he said. "The smell will be gone in a few days." With nowhere else to put them, roughly 40,000 printed bags and 3,500 corrugated cartons had stayed on racks in a corner of the room throughout the job, covered only by plastic sheeting.

Opening day: a smell everyone noticed and nobody mentioned

On the first morning back, the early shift opened the packing room doors and stopped in their tracks. A sharp, glue-like smell with an ammonia edge hung in the air. In the cold room it seemed to sit heavily in place, going nowhere.

By mid-morning, two workers had gone to the first-aid room with headaches and stinging eyes. Others complained of dry, scratchy throats. Everyone pulled up their face masks and kept working, because orders had piled up over the holiday. Worachet brought in six extra industrial fans and assumed things would improve in a couple of days.

Audit day: one carton that changed everything

On day eight, a three-person audit team from the Japanese customer arrived for their scheduled annual inspection. Less than a minute after stepping into the packing room, the lead auditor paused. He asked for a freshly packed carton to be opened, lifted it to his nose, then turned to his colleagues for a tense, quiet conversation in Japanese.

That afternoon the team thawed gyoza samples for a sensory check. They found a faint "chemical-like foreign odour" on both the bags and the product itself. The report recorded a Major Non-conformity for odour contamination risk, and the customer put all shipments on hold immediately until the plant could submit a corrective action plan backed by verifiable evidence.

A chain reaction of losses

• The entire packing line stood idle for six days, with more than 60 staff reassigned to cleaning and stock counts.
• Two containers already booked on a vessel had to be pushed back, bringing rebooking fees and third-party cold storage charges.
• The printed bags and cartons that had absorbed the smell were quarantined, because nobody was willing to sign off on them.
• Head office called every morning for updates, while the contractor kept insisting, "You just need to wait another two weeks."

That night, Arunee stayed late drafting the corrective action report. She knew the Japanese customer would never accept "the smell has probably gone down". They wanted measurable proof that the cause had been dealt with. The question was where that proof would come from, when every lost day meant lost money.

Why Epoxy Floor Odor Hurts Food Businesses More Than You Think

Many plants see post-flooring odour as a short-term annoyance. In food manufacturing, though, a chemical smell is a risk that touches every part of the business, from the health of your workforce to your contracts with buyers.

1. The health of staff who spend whole shifts inside

Packing staff may spend eight to ten hours a day in an enclosed room. Ongoing exposure to volatile organic compounds (VOCs) can cause common symptoms such as:

• Headaches, dizziness and poor concentration
• Irritation of the eyes, nose and throat
• Nausea and general discomfort
• Flare-ups of allergies or asthma in people with existing conditions

Pregnant women, older workers and people with respiratory conditions tend to be more sensitive, and long-term exposure is a concern that health agencies around the world take seriously. When staff feel unwell, absences rise and packing errors follow.

2. Money leaking out every hour the line is down

• Wages that still have to be paid with nothing coming off the line
• Shipping rebooking fees, external cold storage and repeat transport costs
• Quarantined or scrapped packaging, where reprinting custom bags can take weeks
• Frozen raw materials waiting past their planned production window

3. Reputation and audit history

Japanese, European and major retail buyers take odour contamination risk extremely seriously. A single major finding can stay on your supplier record and influence contract renewals or new orders the following year.

4. Fragile trust on every side

• Customers start asking how well the plant really manages risk.
• Employees feel management doesn't care about their health when asked to work through a harsh smell.
• Management and contractors trade blame while the problem stays unsolved.

What Is That Smell in the Packing Room, Really?

Epoxy is an excellent choice for food plants. It is smooth, seamless and easy to clean. But in the weeks after it is poured, the floor keeps releasing chemicals into the air, a process known as off-gassing.

Two-part epoxy and a reaction that isn't finished yet

Most epoxy flooring systems come in two parts: a resin and a hardener. Once mixed, they react and cure into a hard surface. Many hardeners are amine-based, which is where that sharp, ammonia-like note comes from. Some formulations also contain solvents or diluents such as xylene or benzyl alcohol, and the primer and topcoat, which may be a polyurethane (PU) system, can carry solvents of their own.

Why a cold room makes the smell linger

Epoxy cures more slowly at low temperatures. In a packing room held at around 12°C, the floor may not fully cure within the time the contractor expected. Unreacted material keeps evaporating little by little over a longer period, and because the room recirculates its own air, the odour keeps looping around instead of leaving.

Packaging acts like a sponge

Corrugated cardboard is full of tiny pores. Some plastic films can absorb odour molecules, and the foam insulation inside sandwich-panel walls can soak up smells and release them again later. That is why a carton can still smell strongly even after the air seems to be clearing. Fatty foods such as gyoza and fried products also pick up foreign odours more easily than many people realise.

So "epoxy smell" is not one single chemical. It is a mix of many volatile compounds, which can be measured together as TVOC (Total Volatile Organic Compounds), the total amount of volatile organic compounds in the air.

Why the Usual Fixes Fall Short in a Food Plant

During those six days, Worachet's team tried everything they could think of. Here is what they learned.

1. Opening doors and running fans. At home this helps a little, but it takes days or weeks. In a food plant, propping open the packing room door breaks basic hygiene rules. It invites dust, insects and humidity inside and makes temperature control impossible.
2. Air fresheners and fragrance sprays. These only mask the smell for a while. In a food production area, perfume is simply another foreign odour that can taint the product, so it is something to avoid entirely.
3. Activated charcoal and baking soda. They do absorb odour, but their capacity is tiny compared with a room of almost 2,800 cubic metres. They saturate quickly, and you would need enormous quantities to notice any difference.
4. Air purifiers. Most units are sized for small rooms. Their carbon filters saturate fast when faced with heavy VOC loads, and they do nothing about odour trapped inside cartons, insulation and walls.
5. Waiting for it to go away. It sounds like the cheapest option, but porous materials keep re-releasing what they absorbed, so the smell lingers far longer than expected. Meanwhile, every day of waiting is lost production.

What all these approaches have in common is that none of them destroys odour molecules at the source, and none of them produces a number that proves the situation has improved, which is exactly what overseas customers want to see.

The Solution: Ozone Paint Odor Removal for Epoxy Floor Odor in Factories, Powered by the Master Ozone Generator

Arunee went looking for a provider who could show results in numbers, and found the ozone paint odor and chemical residue removal service from World Health Disinfection (WHD). Using the Master Ozone Generator, the service tackles epoxy and PU odours, thinner, lacquer, industrial adhesives and structural steel paint, as well as new-building smells and musty warehouse odours.

How ozone works

The machine releases ozone (O₃), mimicking the way nature purifies air. Ozone is a powerful oxidiser that breaks the molecular bonds of odour molecules, chemical vapours (VOCs) and germs at their source. It destroys the odour rather than covering it up.

Once the cycle ends, any remaining ozone naturally decomposes back into oxygen (O₂), so it leaves no chemical residue and adds no new foreign odour to a production area, which matters enormously in a food plant. As a gas, ozone also spreads throughout the room, reaching dead corners, the undersides of racks and gaps that cloths and ordinary equipment can't get to.

TVOC measured before and after, with calibrated instruments

What convinced Arunee was that WHD measures TVOC on site, both before and after treatment, using an AM1310 meter backed by calibration documents (a KIMO PT100 SC0110 adjusting certificate and a BR-SMART certificate of calibration). That makes WHD one of the few providers in Thailand that shows TVOC reduction results measured at real job sites.

For a plant writing a corrective action report, before-and-after readings like these are hard evidence that speaks far more clearly to a customer than "the smell has gone down".

Fast turnaround for large spaces

Ozone treatment covers large areas in a short time, and once the process is complete the space is typically ready to use within about 2 hours, helping plants plan a faster restart. Every treatment is carried out by trained technicians in a closed, unoccupied space, following clear safety procedures.

10 Reasons Factories Choose WHD for Ozone Odor Removal

1. It destroys odour at the source

Ozone oxidises odour molecules and volatile compounds directly. The smell doesn't creep back the way it does once a fragrance wears off.

2. No chemical residue

Ozone naturally reverts to oxygen, leaving no film, no fragrance and no new smell in your food production area.

3. Before-and-after TVOC results

WHD's ozone chemical residue removal service measures on site with calibrated instruments, so you get data you can attach to a report.

4. Built for big spaces like packing halls and warehouses

Technicians size each Master Ozone Generator cycle to the room's volume, making it well suited to large areas where everyday methods simply can't keep up.

5. Reaches every corner

Because ozone is a gas, it spreads through the whole room, under racks, above ceiling panels and along wall joints where smells like to collect.

6. Back in use quickly

After the process, the area is typically ready within about 2 hours, cutting the time your line spends waiting.

7. Handles many types of chemical odour

Epoxy, PU, thinner, lacquer, industrial adhesives and steel-structure paint are all covered, so it fits almost any factory renovation project.

8. Helps reduce germs and mould in enclosed areas

Beyond chemical smells, ozone treatment also tackles musty odours, germs and mould in closed rooms at the same time.

9. Trained technicians and a clear process

The team surveys the site, protects ozone-sensitive materials and makes sure nobody is inside during treatment.

10. Real industrial experience

WHD's work ranges from condo bedrooms and office meeting rooms to car paint spraying areas and chemical industrial plants. See the details on the paint odor removal service page.

Before and After Ozone Treatment in the Packing Room

How the WHD Team Works

1. Site survey and baseline TVOC check. The team assesses room size and odour sources, and records readings before any work begins.
2. Clear out people, pets and plants. Products and packaging are moved out, and ozone-sensitive items such as natural rubber, artworks or delicate electronics are removed or protected as needed.
3. Seal the area and set up the Master Ozone Generator. Doors and openings are closed, and "no entry" signs go up.
4. Run a cycle sized to the room's volume. Treatment time is matched to the space and the strength of the odour.
5. Allow decomposition and ventilate. Nobody re-enters until the ozone has broken down and the area has been aired out.
6. Re-check TVOC and odour. New readings are compared with the baseline.
7. Hand the space back. It is typically ready to use within about 2 hours of the process finishing.

How the Thara Frozen Story Ended

On day three of the shutdown, the WHD team surveyed the packing room and took baseline TVOC readings. The plant moved all its packaging out to temporary storage, and the technicians sealed the room and ran the treatment after the shift ended. Once the cycle was complete and the room had been ventilated, follow-up readings showed a clear drop in TVOC, and the sharp smell that used to greet staff at the door had faded to a level people could genuinely notice.

Arunee attached the before-and-after results and the calibration documents to her corrective action report, alongside an order for fresh packaging and a newly written procedure for controlling renovation work. After reviewing the documents, the customer allowed packing to resume. The line restarted on day seven, and the delayed containers sailed over the following week.

Worachet later told his team that the real lesson wasn't only about the smell. It was that "you need measurable data before the customer asks for it."

Planning Your Next Epoxy Floor Without a Crisis

• Choose low-VOC materials. Ask your contractor for formulations suited to food production areas and request the safety data sheets.
• Allow enough curing time based on the room's actual temperature, not figures for a standard room.
• Move all packaging and raw materials out. Plastic sheeting is not enough.
• Book ozone treatment before handover and measure TVOC before restarting production.
• Involve QA from day one and keep the readings on file ahead of your next audit.
• Leave a buffer before audits and peak season. Never schedule flooring or painting work in the weeks right before a customer visit or a heavy shipping period, so there is time to treat, measure and fix any issue calmly.

Frequently Asked Questions

Do we need to leave the area during ozone treatment?

Yes. Treatment is only carried out in a closed, unoccupied space. People, pets and plants must stay out for the entire cycle and may return only when the technicians confirm the area is ready.

How long does it take?

It depends on the room size and odour level. Once the process is complete, the area is typically ready to use within about 2 hours. The team will give you a timeline after the site survey.

Does ozone leave anything behind?

Ozone naturally decomposes back into oxygen. Technicians wait for it to break down and ventilate the area before handing it back, so no chemical residue is left.

What size of space is it suitable for?

Anything from a condo bedroom or meeting room to production halls, warehouses and large factories, because each cycle is sized to the room's volume.

Will it remove 100% of the epoxy smell?

Ozone treatment helps significantly reduce and break down volatile compounds, confirmed by real TVOC readings. If the floor hasn't fully cured, the technicians may recommend a follow-up assessment or an additional treatment.

How should we prepare before the team arrives?

Move out products, packaging and ozone-sensitive items, point out any critical equipment, and schedule a time when nobody needs to work in the area.

Related Services and Resources

• Ozone Cleaning Service
• Disinfection Spraying Service
• Ozone Disinfection Machines
• US EPA: Volatile Organic Compounds' Impact on Indoor Air Quality
• WHO: Air Quality, Energy and Health

Just Poured a New Floor or Repainted Your Plant?

Don't wait for your customer to notice the smell first. Let the WHD team survey your site and measure TVOC in your space.

Call 065-556-6294 · LINE @whd268
Email worldhealthdisinfection@gmail.com
88/268 Kanlapaphruek Rd, Bang Khae, Bangkok 10160, Thailand