Large industrial fires can also shut down commuter rail lines in the United States and Canada, as seen today when 125 firefighters were deployed to a massive blaze in south London.
Firefighting response
Around 125 firefighters are fighting a huge blaze in Mitcham.
The fire is affecting a tyre centre, workshop and scaffolding yard, the London Fire Brigade said.
Twenty fire engines are at the scene near Carshalton Road after firefighters were called to the blaze shortly before 4.30pm.
A spokesperson said: "One of the Brigade's 32‑metre turntable ladders has been deployed to help fight the fire from above.
"Control Officers took the first of over 70 calls at 1627 and have mobilised crews from Mitcham, Wallington, Norbury and surrounding fire stations to the scene."
Impact on rail services
The fire has closed the line between Mitcham Junction and Sutton, causing chaos on rush‑hour Southern and Thameslink services.
It told people to avoid the area if they can.
The cause of the fire is not yet known.
Footage shared online shows smoke billowing from the fire as firefighters battle the blaze.
The local authority Merton Council wrote online: "London Fire Brigade are responding to a large fire in the Mitcham Junction area.
"Please avoid the Carshalton Road area. Trains are suspended between Mitcham Junction and Hackbridge.
At this time no casualties have been reported. The cause of the fire is under investigation."
In North America, similar incidents have forced transit agencies to suspend services, underscoring how fire safety can directly affect daily commuters.
Authorities in both countries monitor such events closely to minimise disruption and protect public health.
This is a developing news story and is being updated.