Apparently, parts of the Washington, DC metro rail line have become so caked with layers of human hair that it presents a fire hazard.
Close-up of hair fibre accumulation
“I was flabbergasted — flabbergasted — at the amount of hair that’s in the Metro,” said Brian Sherlock, a safety specialist for Amalgamated Transit Union.
“Hair literally comes off of people and off of clothing and gets sucked up."
The hair gets sucked up into the tunnel, and collects on insulators that house the electric third rail. The felt-like lining is 1/8 inches thick in some places, and could pose a fire risk by trapping heat.
