WASHINGTON (DC News Now) — Some Metrorail passengers could find their trips a little longer this week due to the heat.

The transit agency monitors the temperatures of its rails, particularly those above ground. Should they top 135 F, the speed is reduced to 35 miles per hour as the high temperatures can cause steel rails to expand and buckle, which can lead to derailments.

The slower speeds mean longer travel times to destinations.

“I am kind of worried about that because I ride the subway a lot and I need the subway to get around,” Sylvester Taylor, a regular passenger, said.

Metro did not respond to requests to comment on how it plans to deal with the heat, but it said in the past, maintenance crews will conduct frequent inspections of above ground rails to make sure they are safe.

“It’d be messing with my money, me getting back and forth to work,” said Camron Johnson, another passenger concerned about potential delays. “So hopefully. No.”

Just over 275,000 people ride Metrorails every day, according to the latest figures from Metro.

Though not everyone is worried about longer travel times.

“They’ve done a lot of work to Metro over the last couple of months. I see the improvement,” said Karen Smith.

Smith and other riders will be able to enjoy chilled water mixed in with the air, or Chillers, while waiting to board amid the heat.