Major fire shut the Hillhouse chemical plant for three months. The community was never told.

There was no news of this fire, because there was no announcement. We found it in the company’s own accounts. What follows is drawn from AGC’s own filings, from public safety regulations, and from the published chemistry of the process involved. The questions we raise, we leave for AGC and the regulators to answer.

What the accounts record

In its 2024 accounts, filed at Companies House, AGC Chemicals Europe records that “the business experienced a fire in October 2024 within the Steam Pyrolysis section of the plant,” and that this “caused an outage of 3 months.” A separate note confirms the date, “an incident on 19 October 2024 where a fire occurred at the Company premises,” and that the company is claiming on its insurers for “income lost directly attributable to this incident.”

So there was a fire, at a chemical plant on a residential fenceline, that stopped part of the works for three months. It was written down for shareholders. As far as we can find, it was told to no one else.

We looked for any public trace of it. There is none.

No local news report. No fire-service statement. No entry we could find on any public register. For an event of this length at a site that is otherwise closely watched over its history of contamination, that silence is itself remarkable. The only public record of this fire appears to be a sentence in a financial document written for the City.

What the “Steam Pyrolysis section” is, and why it matters

At a fluoropolymer plant, steam pyrolysis is not a minor process. It is how the raw material is made. The monomer that Fluon and similar products are built from, tetrafluoroethylene, is produced by the high-temperature steam pyrolysis of a feedstock gas at around 650 to 800 degrees Celsius. In other words, this is very likely the chemical heart of the plant, the unit that makes the building block everything else depends on. That the whole works stopped for three months points to exactly that.

It also means this is arguably the most hazardous process on the site. The published chemistry of making this monomer is associated with some of the most acutely dangerous substances handled anywhere in the industry: hydrogen fluoride, and perfluoroisobutene, a compound so toxic that it is controlled under international chemical-weapons rules. We are not saying any of these were released. We are saying this is the part of the plant where they belong, and it is the part that caught fire.

(We have identified the unit from its name and from the standard chemistry of fluoropolymer manufacture. AGC can confirm or correct what the Steam Pyrolysis section does.)

What the rules require, and what they do not

AGC Hillhouse is a major-hazard site, listed by the Health and Safety Executive as a lower-tier establishment under the Control of Major Accident Hazards Regulations. Under separate safety law, RIDDOR, a fire that suspends normal work for more than 24 hours is a reportable “dangerous occurrence.” This fire suspended work for about three months. On the face of it, then, it should have been reported to the HSE, and a record should exist.

But here is the gap. There is no duty on a lower-tier operator to tell the public. So the regulator was, in all likelihood, informed. The shareholders were informed. The people living against the fence were not, and no law obliged the company to tell them.

It was not always this way

Within living memory, this area ran chemical-emergency drills in its local schools, from a time when the site sat under a stricter regime with plans to warn its neighbours. A serious fire now passes without a word. That raises a fair question: has this site’s duty to warn the community quietly lapsed, even as its most hazardous process kept running next door to homes?

“The community and the environment”

AGC’s own 2024 accounts state that its directors weigh “the community and the environment,” and the company’s reputation for high standards, in how they run the business. A three-month fire that the community was never told about is that stated commitment set against that silence.

The questions we are asking, and think you should too

• What burned, and what came off it? Was the surrounding air monitored during the fire and its aftermath?
• Was the fire reported to the HSE and the Environment Agency, as the rules appear to require?
• Did the fire service issue any advice to nearby residents at the time?
• Why was the public not informed of a three-month fire at a major-hazard chemical plant on a residential boundary?
• And is a warning regime that requires nothing to be said to the neighbours adequate for a plant on a fenceline?

We do not have the answers. We are asking the bodies that should. We will publish what they tell us, and we will publish it just as plainly if they tell us nothing.

How we know what we know

The fire: AGC Chemicals Europe Ltd accounts, Companies House company 03825057 (the going-concern note and the contingent-asset note in the 2024 filing). The site’s status: HSE’s public COMAH establishment lists. The reporting rule: HSE guidance on RIDDOR dangerous occurrences. The chemistry: the published safety literature on tetrafluoroethylene manufacture. Every one of these is public, and we will point you to it.