Fatigued driver asked to take an overnight trip
A 38-year-old PSV driver started at 04:30, drove Nairobi to Nakuru and back, and by 18:30 has been on duty for 14 hours, with 9 hours at the wheel and two 25-minute breaks. He has a heavy cold and took chlorphenamine at 15:00. Dispatch now asks him to take a 22:00 overnight bus to Mombasa, a 480 km trip, because the relief driver has not reported. He has had no proper meal since midday and feels sleepy, but he needs the allowance. The bus is roadworthy and has a conductor. The operator says the trip is important and that the driver can 'drink strong coffee and open the window'. He is due to return at 08:00. The route includes a long, monotonous section after midnight.
1. Assess the driver's fitness for the 22:00 trip. Identify the factors that make him unfit, not just tired.
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The driver is not fit for the trip. By 22:00 he will have been awake for about 18 hours, after 14 hours on duty and 9 hours at the wheel with only short breaks. That creates significant sleep pressure. The 22:00 start also falls in the evening period when alertness naturally drops, and the long monotonous section after midnight increases the risk of microsleeps.
His cold and the chlorphenamine he took at 15:00 make the risk worse. Chlorphenamine is a sedating antihistamine; it can cause drowsiness, slowed reactions and poor concentration, and its effects may still be present at 22:00. He has also not eaten properly since midday. Coffee and an open window are short-term measures that do not reverse fatigue or drug sedation. Fatigue is an impairment: it slows hazard perception and decision-making. The driver should be assessed as unfit, even if he feels he can 'push through'.
2. What should the driver do, and what should the operator do when he reports unfit?
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The driver should report unfit for duty before departure and should not take the bus. He should explain the duty hours, the sedating medicine and his sleepiness, and ask for the trip to be reassigned. He should record the report so that there is a clear trail. He should not be persuaded to 'try' the first section or to drive until he feels sleepy; fatigue can become overwhelming without warning.
The operator should arrange a rested, qualified driver, delay the trip, or cancel it and rebook passengers. It should not pressure him or offer inducements to drive. The operator should also review the scheduling that produced 14 hours on duty and should check whether the driver received advice about driving while taking sedating medicine. If no relief driver is available, the safe outcome is a delay or cancellation, not a departure with an impaired driver. The conductor should not be asked to substitute for the driver.