What is a Fog Light (Sis Farı)?\n\nFog lights, known in Turkey as 'sis farı', are specialized lighting devices designed to improve road safety during periods of severely restricted atmospheric visibility. Unlike standard headlights, which project light at an angle that can reflect off water droplets in fog and blind the driver, fog lights are mounted low on the vehicle's front bumper. They emit a wide, flat bar of light that shines parallel to the road surface, illuminating the lane underneath the low-hanging layer of fog. Understanding how they operate and when to activate them is essential for both the Turkish MTSK e-sınav (driving theory exam) and safe daily driving across Turkey's diverse mountain passes and coastal highways.\n\n## Official Turkish Traffic Rules and Legal Restrictions\n\nUnder the Turkish Highway Traffic Regulation, the use of fog lights is strictly controlled. Drivers are legally permitted to activate their front and rear fog lights only during conditions of dense fog, heavy snowstorms, or torrential rain where visibility is critically reduced. Using fog lights during normal nighttime driving, light rain, or clear weather is a direct traffic violation. Under Highway Traffic Law No. 2918, violating this rule leads to an administrative traffic fine (idari para cezası) and penalty points on your driver's license. This restriction exists because the intense, unfocused beam of fog lights easily dazzles oncoming motorists, significantly increasing the risk of accidents.\n\n## MTSK Exam Preparation and Common Test Pitfalls\n\nIn the Turkish driving theory exam (ehliyet sınavı), questions regarding vehicle lighting and safety regulations are highly common. Candidates are often tested on scenarios where they must choose the correct light to activate under specific environmental conditions. A classic trick question asks whether it is acceptable to use fog lights to increase visibility on dark, unlit rural roads at night during clear weather. The correct answer is always no—high-beam headlights should be used in these situations instead, provided there is no oncoming traffic. Additionally, in the practical driving exam, examiners will expect you to locate the fog light switch and identify the corresponding dashboard symbols: front fog lights point left with a wavy line crossing the vertical beam, while rear fog lights point right with a similar wavy line.\n\n## The Danger of Dazzling Other Road Users\n\nOne of the primary reasons Turkish traffic police enforce fog light violations so strictly is the hazard of glare. Because front fog lights are positioned low and have wide-angle lenses, their light scatters widely. When roads are wet from rain, this light reflects off the tarmac, creating a blinding glare for oncoming drivers. Furthermore, rear fog lights are significantly brighter than standard tail lights—similar in intensity to brake lights. Keeping them on when it is not foggy can confuse drivers behind you, mask your actual brake indicators, and cause severe eye strain, potentially triggering catastrophic rear-end collisions.