The VRE Rider’s Encyclopedia

Ever see an alert a Train Talks Alert and think, “What does that even mean?” As cooler weather rolls, some new rail terms start to pop up. This short glossary explains the phrases you’re most likely to encounter riding VRE this fall—what they mean and why they matter to you. 

Fall Terms 

Leaf Oil: When fallen leaves mix with rain and are crushed by passing trains, they release a slippery residue called “leaf oil.” It can make tracks slick, so trains may slow down to stop safely. If you notice a slight delay in the fall, this is often why. 

Rail Safety Week: A nationwide campaign that highlights safe choices around tracks and trains. During this week in September, keep an eye out for extra outreach from VRE and safety reminders on social media. “See Tracks? Think Train.” 

Year-Round Terms You’ll Still See 

PTC: Positive Train Control aka PTC is a nationwide safety system that helps keep trains operating safely by monitoring rail conditions and train movements. These systems are designed to prevent train-to-train collisions.  

Switch Issues: A “switch” is the part of the track that lets trains move from one rail line to another. Weather, ice, or vibrations can cause it to malfunction. Until it’s fixed, crews may have to slow down or manually adjust the switch, which can delay service. 

Extended Service: VRE’s plan to expand train frequency and add weekend service. Riders often ask about it—there’s no launch date yet, but updates will be shared as soon as they’re available. 

Have a rail term you’d like explained? Comment below and help us expand our VRE encyclopedia. This fall you might notice these phrases popping up in Train Talk alerts. Our goal is to make those messages clearer, so you can travel confidently and know what’s happening behind the scenes.