Heathrow Terminal 4 Evacuated After Possible Hazardous Material Incident
On the evening of September 8, London Heathrow Airport’s Terminal 4 was evacuated due to a report of a “possible hazardous materials incident.” Emergency services, including firefighters and paramedics, responded immediately, and passengers were advised to avoid the terminal. Operations were restricted only to Terminal 4, while the rest of Heathrow functioned normally. Fortunately, no flights were disrupted, and the terminal has since resumed operations. The Metropolitan Police later clarified that no hazardous substances were found.
Three-Hour Closure and Investigation
The incident began at around 17:00 local time, as reported by CNN. The London Fire Brigade was alerted to a potential hazardous situation at Terminal 4. Units from various nearby stations, including Feltham and Wembley, were dispatched alongside specialist teams to conduct assessments. As a precautionary measure, the entire check-in area was cleared during the investigation. Approximately three and a half hours later, the terminal was deemed safe, and Heathrow confirmed its operational status. Despite over 20 individuals reporting minor injuries, none were life-threatening or severe. The incident is suspected to have been a case of “mass hysteria.”
Flights Remained Unaffected
No disruptions to flights were reported during the Terminal 4 incident. The terminal, situated south of the airport’s runways near the cargo complex, accommodates numerous international carriers, including:
- Aeromexico
- Air France
- Bulgaria Air
- China Southern
- Etihad Airways
- Gulf Air
- KLM
- Korean Air
- Qatar Airways
- Saudia
- Vueling
- WestJet
In addition to airlines, Terminal 4 hosts several premium lounges such as those operated by Gulf Air, Malaysia Airlines, and Qatar Airways, along with the SkyTeam lounge, which serves passengers flying with designated member airlines.

Terminal 4’s Role at Heathrow
Terminal 4 is integral to handling long-haul and transfer traffic at Heathrow. It was shut down for two years due to the COVID-19 pandemic and reopened on June 14, 2022, following significant refurbishments to enhance passenger amenities.
Power Outage Disruption Earlier This Year
Earlier, on March 21, a severe power outage caused by a fire at a nearby electrical substation prompted Heathrow to halt operations entirely. This incident led to the cancellation of over 1,000 flights and affected approximately 270,000 passengers. Airports across Europe and the United States managed redirected flights as Heathrow resolved the crisis.