Pre-Trip With 38 Students Already Boarding
Monday, 6:55 a.m. Bus 14, a 54-passenger air-brake bus, is in the lot with 38 students boarding for a 7:05 departure. During the pre-trip you find: the low-air warning buzzer sounds at 62 psi; with the engine at fast idle, pressure builds from 85 to 100 psi in 70 seconds; the left rear inner tire has 3/32 inch tread; the emergency door buzzer does not sound when the door is opened; and the left stop-arm bulb is out. Outside temperature is 38°F and roads are dry. The dispatcher says the spare bus is 25 minutes away and the first stop is a preschool.
1. Classify each finding as a no-go defect, a defect that must be corrected before the route but may be quick, or a condition to monitor. Explain your reasoning.
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The slow air build is a no-go: a typical air-brake check expects 85 to 100 psi within about 45 seconds, and 70 seconds means the compressor or governor system needs attention before the bus carries passengers. The inoperative emergency door buzzer is also a no-go because it removes a warning that an exit is open. The stop-arm bulb is a required safety device; it must be repaired before a route with student stops, though it may be a quick bulb replacement. The 3/32 inch rear tire is above the usual 2/32 inch rear minimum but below a common 4/32 inch school-bus replacement target; document it and replace it soon rather than treating it as the sole reason to cancel. The low-air buzzer at 62 psi is late but still in the warning range; note it for the shop.
2. What do you do with the students while the bus is defective, and what do you tell dispatch?
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Do not depart. Keep students in a supervised, safe staging area, not in the defective bus and not loose in the lot. Tell dispatch specifically: air build is 70 seconds, emergency door buzzer is inoperative, stop-arm bulb is out, and the rear inner tire is at 3/32 inch. Ask whether the spare can be moved up, whether a mechanic can fix the buzzer and bulb at the lot, and whether the preschool stop can be covered. Tell students only what they need to know: the bus is not safe to move yet and they will board when it is cleared. Notify the school of the delay. A 25-minute wait is inconvenient; an unsafe bus is not an acceptable alternative.
3. If the only defect were the burned-out stop-arm bulb, could you run the route and report it later? Why or why not?
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No, not as a normal school-bus route. The stop arm is part of the loading-zone warning system, and a burned-out bulb reduces what other drivers can see when students cross. The correct action is to have the bulb replaced or use a spare bus before the route. If no replacement is possible and the route has no student crossings, a supervisor might authorize a limited movement, but that is an operational decision above the driver. The driver should not unilaterally decide that a required warning device is optional because the route is running late.