Pavement Markings: Practice Questions & Explanations

A solid white line on the right edge of the road is the 'fog line' that marks the right edge of the traveled roadway. To its right is the shoulder, which is for emergency stopping, not normal travel. Crossing the fog line consistently is a sign of driver fatigue or distraction. Fog lines also help drivers stay in their lane in fog, snow, or at night when visibility is reduced. Some highways have audible 'rumble strips' along the fog line that make a loud noise if a tire crosses, alerting a drowsy driver before they leave the road. Crossing the fog line to pass slower traffic on the right is generally illegal and unsafe.

Broken (dashed) white lines separate two lanes traveling in the same direction. They indicate lane changes are permitted when safe — when there is room, no vehicle in the lane you are moving to, and visibility allows. Solid white lines between two lanes of the same direction discourage but do not necessarily prohibit lane changes; treat them as 'do not cross unless you really need to'. Yellow lines (in either solid or broken form) separate traffic moving in opposite directions: broken yellow allows passing when oncoming traffic is clear; solid yellow on your side prohibits passing across the line. Double solid yellow prohibits passing in both directions.

Double solid yellow lines (two solid yellow lines side by side) prohibit passing in both directions. The line marks a section of road where sight distance, curve, hill, or intersection density makes passing unsafe regardless of which direction you are going. You may not cross double yellow lines to pass another vehicle, even if the oncoming lane appears clear. You may cross briefly for turns into driveways or side streets where this is permitted, and some states allow crossing to overtake bicycles when safe. One solid and one broken yellow line means passing is permitted from the side with the broken line, prohibited from the side with the solid line — passing rules apply only to your side.

A diamond shape painted within a lane marks that lane as restricted-use. Most commonly it indicates an HOV (high-occupancy vehicle, or 'carpool') lane that is restricted to vehicles with two or more occupants during certain hours. Diamond markings can also indicate bus lanes or bicycle lanes depending on local convention; usually a sign accompanies the marking to specify the rule. HOV lanes are typically the leftmost lane on a highway and are intended to reduce congestion by rewarding carpooling. Violating HOV restrictions carries fines, and many HOV lanes are now monitored by automated enforcement. Outside posted hours, some HOV lanes open to all traffic; check signage carefully.

DOUBLE SOLID YELLOW CENTRE LINE: Neither side may cross for passing. This marking appears where passing is too dangerous from either direction due to: limited sight distance; curves; hills; construction zones. SINGLE SOLID YELLOW: On your side means you may not pass; other side may be able to (depends on their marking). SINGLE BROKEN YELLOW: Passing permitted (when safe and legal). BROKEN YELLOW + SOLID YELLOW: The side with broken yellow may pass; the side with solid yellow may not. DOUBLE BROKEN YELLOW: Rare; reversible lane marking. YOU MAY CROSS DOUBLE YELLOW LINES TO: Make a left turn into a driveway or parking area; enter or exit a HOV lane (if pavement marking indicates entry/exit); avoid an obstacle or emergency. You may NEVER cross double yellow lines to PASS another vehicle.

WHITE EDGE LINE (RIGHT EDGE LINE): A solid white line running parallel to the road on the right side marks the boundary between the travel lane and the shoulder. Key rules: DO NOT DRIVE ON THE RIGHT SIDE OF THIS LINE except for emergency stops or specifically designated right turns; the edge line helps drivers stay in their lane in poor visibility (rain, fog, night); BIKE LANES are separated from the travel lane by a solid white line, but will also have 'BIKE LANE' text or a bicycle symbol; RUMBLE STRIPS are often placed near or at the edge line — feeling vibration means you're drifting off the roadway; SHOULDER: The area beyond the edge line is the shoulder — not a travel lane (except in specific HOV or emergency-only shoulder use designations during peak hours on some highways).

Yellow lines separate traffic moving in opposite directions on a two-way road. A solid yellow line on your side of the center means you may not cross it to pass — passing is prohibited there. A broken (dashed) yellow line on your side means passing is permitted when it is safe. Where there are two lines, a solid line paired with a broken line means passing is allowed only for the side with the broken line. Double solid yellow lines prohibit passing in both directions. Understanding yellow center-line markings — solid means no passing, broken means passing allowed when safe — is essential pavement-marking knowledge.

White pavement markings separate lanes of traffic traveling in the same direction and mark the right edge of the roadway. A broken (dashed) white line between lanes means you may change lanes when it is safe; a solid white line discourages or prohibits lane changes and is often used near intersections or to mark the edge line. By contrast, yellow lines separate opposing traffic. Recognizing the difference — white for same-direction lanes and road edges, yellow for opposing traffic — helps a driver understand the roadway layout. Pavement markings are a tested part of the road-signs section.