South Australia · The Driver's Handbook · chapter 4 · 14 min read

Sharing the Road & Hazardous Situations

Driver Fatigue

It is recognised that fatigue is more likely to be a factor in crashes in rural areas as they can involve long trips and extensive periods of continuous driving; however, anyone can be affected by fatigue, even when driving in the city or suburbs.

Driver fatigue is particularly dangerous because one of the symptoms is decreased ability to judge your level of tiredness. Research has shown that not sleeping for more than 17 hours has an effect on driving ability the same as a Blood Alcohol Concentration (BAC) of 0.05. Not sleeping for 24 hours has the same effect as having a BAC of 0.10, double the legal limit.

If you don’t get enough sleep you will go into sleep debt and will ‘owe’ yourself more sleep. The only way to repay this debt is by sleeping. Until you catch up What causes fatigue? on your sleep, before The main causes are: driving, you will have a

• lack of quality sleep greater risk of having a fatigue-related crash.
• time of day – driving when you would normally be sleeping (eg 1am-6am) or in the afternoon period (eg 1pm-5pm) when our biological time clock makes us feel tired
• length of time performing the task
• sleeping disorders such as sleep apnoea.

How do I avoid fatigue?