Narrowing to the Left Cladding Sheet Sign T-4C

Narrowing to the Left Cladding Sheet Sign (T-4C)

The Narrowing To Left Cladding Sheet Sign (T-4C) is a warning sign used to indicate situations where passage is not possible on either side of the road or from the right. This sign informs drivers about sections where the road narrows or passage is restricted and reminds them to comply with the prohibitions indicated by other traffic signs. Since the T-4C sign serves as a hazard warning, it is designed with black symbols inside a red triangular frame. The T-4C sign falls under the category of hazard warning signs and is represented by a black symbol within a red equilateral triangle. According to the General Directorate of Highways standards, these signs are produced in sizes of 60 cm, 75 cm, and 90 cm. To enhance nighttime visibility, the signs are made of reflective material.

Hazard warning signs aim to inform road users of potential dangers and ensure they take necessary precautions. These signs remind drivers to be more cautious and control their speed. Typically shaped as equilateral triangles, these signs are coded with the letter "T."

Traffic regulation signs, on the other hand, are used to ensure the orderly flow of vehicle traffic. These signs are denoted by the letters "TT" and indicate actions that are permitted or prohibited on the road. For example, signs such as maximum speed limits, yield, or no bicycle entry fall under this category. These signs provide traffic-directing information.

1. Definition and Purpose of the Sign

The T-4C sign is a hazard warning sign that alerts drivers to an upcoming dangerous curve to the right on the road.

This sign is used to ensure drivers reduce their speed, stay alert, and comply with other traffic rules.

2. Visual Characteristics of the Sign

Shape: Equilateral triangle.

Color: Black symbol inside a red border. The background is white.

Symbol: Designed as an arrow curving to the right.

Reflective Feature: Made of reflective material to ensure visibility at night or in low-visibility conditions. Reflective properties are available in:

Normal Performance Reflective,

TYPE 1 Reflective,

TYPE 4 Reflective (Economical),

TYPE 4 Reflective (compliant with KGM standards).

3. Dimensions of the Sign

According to the General Directorate of Highways standards, the T-4C sign is produced in three sizes:

60 cm: Typically used on narrow roads or in residential areas.

75 cm: Preferred for medium-sized roads.

90 cm: Used on wide roads, highways, or areas with high-speed limits.

4. Installation and Placement

Height: The sign is mounted approximately 2 meters above the road surface.

Distance: Placed at a sufficient distance before the curve to allow drivers to notice the warning and take necessary precautions. The distance is determined based on the road's speed limit:

For 50 km/h speed limits: 50-100 meters before the curve.

For 90 km/h speed limits: 150-200 meters before the curve.

Visibility: The sign is placed in a location where drivers can easily see it, ensuring no obstructions block the view.

5. Standards and Regulations

In Turkey, this sign is produced and used in compliance with the Highway Traffic Regulation and General Directorate of Highways (KGM) standards.

International Standards: The T-4A sign is designed in accordance with the Vienna Convention on Road Signs and Signals.

6. Areas of Use

Rural roads: Areas with sharp curves.

Mountainous areas: Roads with frequent curves and steep slopes.

Highways: High-speed zones requiring curve warnings.

Residential areas: Dangerous curves within settlements.

7. Other Features

Durability: Signs are made of materials resistant to weather conditions (rain, snow, wind, sunlight, etc.).

Maintenance: Periodically checked, and damaged signs are replaced.

Local Language Support: In Turkey, standard Turkish symbols and signs are used.