The Mirror You Didn't Check
You are driving a 40-foot straight truck on a four-lane divided highway at 60 mph in the right lane. You have been on the road for 9 hours, with a 30-minute break, and it is 2 a.m. Your phone is mounted on the dash and has buzzed three times in the last ten minutes. You need to exit in 2 miles, and a sign for the exit is coming up on the right. Traffic is light. Your eyes feel heavy, and you notice you have drifted toward the rumble strip twice in the last few minutes without consciously correcting.
1. What is the most important hazard in this situation, and why isn't it the phone?
Read the worked answer
The most important hazard is your own fatigue - the phone is a symptom, not the disease.
The drift onto the rumble strip is the key fact. Drifting without noticing means you are having micro-sleeps; your brain is briefly going offline. At 60 mph you cover 88 feet per second, so a two-second lapse is nearly 200 feet of driving blind. That is the mechanism behind most run-off-the-road and rear-end crashes at night.
- Nine hours driving with one 30-minute break is well past the point where alertness holds up, and 2 a.m. is the low point of the body's clock.
- The phone buzzing is a distraction, but silencing it does not fix the fatigue. It just removes one more thing competing for attention you do not have.
- The exit in 2 miles is not worth pushing for. The right move is to take the next safe opportunity to stop and rest, not to gut it out to the exit.
2. You decide to continue the 2 miles to the exit. What should you do differently for those 2 miles, and what is the risk of that plan?
Read the worked answer
If you continue, you must treat it as a degraded-operation segment, not business as usual - and you should recognize the plan carries real risk.
What to do:
- Silence the phone completely, not just ignore it.
- Increase following distance well beyond normal; at 60 mph that means a much larger gap than the usual rule of thumb.
- Keep both hands on the wheel and your eyes moving - mirror, ahead, mirror - rather than fixed on the exit sign.
- Reduce speed somewhat; lower speed buys reaction time and reduces crash energy.
- Signal early and set up for the exit well in advance so you are not making a late lane change.
The risk: none of this restores alertness. It only reduces the chance that a lapse becomes a crash. The honest assessment is that the safest plan is to stop at the first safe place, even before the exit, rather than to manage a known impairment for 2 miles.