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Zorluk: OrtaDriving in Fog

While hauling freight across a low river basin at dawn, a commercial driver encounters dense fog that limits forward visibility to 200 feet, and surface moisture coats the pavement. Which operational procedure should the driver follow to maintain safe vehicle control?

  1. A
    Engage the auxiliary engine retarder to maximum power to assist braking on the slick surface and turn on high-beam headlights to pierce the fog.
  2. B
    Reduce following distance to closely shadow the taillights of a lead vehicle as a primary visual guide through the fog.
  3. Adjust vehicle speed to ensure the total stopping distance remains within visible sight range, disengage the engine retarder, and use low-beam headlights.Cevap
  4. D
    Maintain normal highway speed provided the mechanical braking distance alone matches the 200-foot visual range, disregarding perception and reaction distances.

Cevap

Adjust vehicle speed to ensure the total stopping distance remains within visible sight range, disengage the engine retarder, and use low-beam headlights.
Safe commercial vehicle operation in fog requires adjusting travel speed so that total stopping distance is strictly less than the forward sight distance, utilizing low-beam headlights to minimize blinding glare reflection, and switching off auxiliary retarders to prevent drive-wheel skids on road moisture.

Adım Adım Çözüm

1
Assess speed and total stopping distance relative to sight distance.
Vehicle speed is reduced until total stopping distance (perception + reaction + braking) is well within the 200-foot visibility limit.
Federal CDL safety rules mandate that drivers must always be capable of stopping within the clear distance visible ahead.
2
Select proper lighting and auxiliary brake settings.
Low-beam headlights are activated and the auxiliary retarder is turned off.
Low beams prevent hazardous glare reflection from water droplets, while turning off retarders prevents drive wheels from breaking traction on wet road surfaces.

Anahtar Kavram

Fog driving speed management, low-beam illumination, and retarder disengagement on wet pavement
Tahmini Süre:1m 15s
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Konular

Driving in Fog

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