School Bus: Mirrors

4 questions in the bank cover this topic. Everything below is drawn from the sources those questions cite.

Sources: 49 CFR 571.111

What you need to know

FMVSS 111 S9.1 requires two distinct systems.

System A gives the rearward view down each side; System B covers the areas around the bus that the driver cannot see directly, which is where children are.

Each school bus shall have two outside rearview mirror systems: System A and System B.

49 CFR 571.111

FMVSS 111 S9.2(a) requires a flat, unit magnification mirror of at least 323 square centimetres per side, plus one or more mirrors giving the specified ground view.

At least one is required, measured as reflective surface. Measured as reflective surface.

Includes at least one mirror of unit magnification with not less than 323 cm

49 CFR 571.111

FMVSS 111 S9.3 defines System B by the cylinders around the bus whose tops the driver cannot see directly.

These are the crossover mirrors, and the cylinders stand in for a child. Its view must also overlap System A's ground view, leaving no blind gap. Those are the areas not directly visible from the driver's seat.

For each of the cylinders A through P whose entire top surface is not directly visible from the driver's eye location, System B shall provide, at that location: (1) A view of the entire top surface of that cylinder.

49 CFR 571.111

FMVSS 111 S2 states it in terms of deaths and injuries from an obstructed rearward view.

On a school bus that risk is concentrated in the danger zone immediately around the vehicle. The standard is aimed at drivers without a clear, reasonably unobstructed view to the rear.

The purpose of this standard is to reduce the number of deaths and injuries that occur when the driver of a motor vehicle does not have a clear and reasonably unobstructed view to the rear.

49 CFR 571.111

Check yourself

• How many outside rearview mirror systems must a school bus have?

• What does System A on your school bus require on each side?

• System B on your school bus is for ______.

• What is the stated purpose of your mirror standard?

Answers are in the practice test for this topic.