Roadside & Legal · Driver Training VideoWarning Triangles & Unauthorized Lights

Part one: warning devices when you're stopped. If your rig is stopped on the traveled part of the highway or the shoulder — for any reason other than a quick, necessary stop — federal rule says you put out warning devices within 10 minutes. Not when you get around to it.

What you deploy are three bidirectional reflective warning triangles. Flares or fusees are an allowed alternative, but triangles are the standard, and they're what you should have on the truck.

On a normal two-lane road: one triangle on the traffic side, about 10 feet behind the truck. One about 100 feet behind, in the center of the lane or shoulder, facing approaching traffic. One about 100 feet in front.

Two special cases

Within 500 feet of a hill, curve, or anything blocking your truck from view, move that rearward triangle back — 100 to 500 feet — so drivers coming up on you have time to react.

You're required to carry at least three reflective triangles at all times. Check them on your pre-trip. "No triangles deployed" is a real citation, it hits your CSA vehicle maintenance score, and it can put you out of service.

Part two: unauthorized and flashing lights. Your company standard: your tractor shows only the lamps, colors, and positions the regulations authorize — nothing else.

Flashing white, red, or blue lights are not allowed on a commercial tractor. Those colors and that flash pattern are reserved for emergency vehicles, and running them is a citation that can put you out of service.

Allowed: amber for front and side markers, turn signals, and your four-way hazards. Red for rear markers, tail, brake, and rear turn signals. White for headlights and legal, non-flashing work lamps. Just the required lamps, required colors, all working.