White = centre line, edge line, lane markings, pedestrian crossings. Yellow = no-parking zones, median barrier, speed bumps. White broken = overtaking permitted. White continuous = no overtaking.

IRC 35:2015 specifies colors for clarity and safety. White is typically used for lane lines, edge lines, and channelizing devices, indicating traffic moving in the same direction. Yellow is used to separate traffic flowing in opposite directions and to mark the right edge of the roadway. Red is used for specific warnings or prohibitions, such as on traffic islands or at hazardous locations.

Road studs are classified based on their retroreflective properties. Class 'A' studs have a minimum retroreflective coefficient (RA) of 300 cd/lx/m² at an initial 0 degree angle for white studs, suitable for high-demand areas. Class 'B' studs have a lower RA of 150 cd/lx/m². Colored studs like red, yellow, blue, and green also have specified minimum RA values to ensure visibility in their intended applications.

A broken centre line, characterized by a repeating pattern of lines and gaps, indicates that overtaking is permitted under safe conditions. The standard ratio for a 3m line pattern is 3m line to 3m gap. A solid centre line signifies that overtaking is prohibited. Solid centre lines are typically used on stretches with restricted visibility, steep gradients, sharp curves, or at approaches to intersections and pedestrian crossings.

The application method and material choice depend on the pavement type. For asphalt surfaces, ensure it is clean and dry. For concrete pavements, surface preparation might involve cleaning and possibly etching to ensure good adhesion. The expansion and contraction characteristics of the pavement should also be considered to prevent premature failure of the markings.

In areas prone to heavy rainfall or fog, highly visible and durable markings are essential. Retroreflective materials, especially those with good luminance factors in wet conditions, are crucial. Raised pavement markers (road studs) also improve visibility during adverse weather. The choice of material should prioritize visibility and longevity under challenging conditions.

The luminance factor (β) is a measure of how well an unlit surface reflects incident light, indicating its brightness under normal daylight. A high luminance factor means the marking is more visible during the day. IRC 35:2015 specifies minimum luminance factors for white (0.85) and yellow (0.45) materials to ensure adequate daytime visibility, which is critical for driver perception.

Pedestrian crossing markings, commonly known as zebra crossings, typically consist of parallel white stripes. According to IRC 35:2015, the minimum width of these lines is 150 mm. The stripes are laid across the road surface, with a minimum spacing of 300 mm between them, ensuring a clear and visible zone for pedestrians.

Pavement messages are used to convey specific information or instructions to drivers. Symbols like arrows guide traffic flow, while legends like 'SCHOOL' warn of specific zones. IRC 35:2015 specifies dimensions for these messages to ensure they are legible from a safe distance. For example, the height of legend characters for messages like 'SCHOOL' is recommended to be a minimum of 2.4 meters.

While IRC 35:2015 provides performance requirements, the frequency of inspection and maintenance is often site-specific and dictated by local road authorities and project specifications. However, regular visual inspections should be conducted, especially after adverse weather events or significant traffic incidents. Prompt replenishment or remarking of faded or damaged markings is crucial for maintaining road safety.

IRC 35:2015 outlines stringent quality control measures. This includes testing for material properties like retroreflectivity, luminance factor, durability, skid resistance, and adhesion. Manufacturers are expected to provide certificates of conformity, and random testing can be performed by the road authority to ensure compliance with the specified standards.

The classification of road studs into Class 'A' and Class 'B' is based on their performance and expected lifespan in varying traffic conditions. Class 'A' studs, with higher retroreflectivity, are intended for high-speed roads, major intersections, and areas where enhanced visibility is critical. Class 'B' studs are suitable for lower-speed roads or areas where slightly reduced visibility is acceptable, offering a more economical solution.

IRC 35:2015 indirectly addresses drainage issues by emphasizing the durability and adhesion of marking materials. Poor drainage can lead to water saturation, freeze-thaw cycles, and chemical attack, all of which degrade markings. While the code doesn't mandate specific drainage improvements, it requires materials that can withstand these harsh conditions. Selecting appropriate materials with good water resistance and ensuring proper surface preparation are key to longevity in such areas.