An Investigation of Heart Rate and Oxygen Saturation Level (SpO2 ) in Indicating Driving Fatigue

Introduction: In Malaysia, the number of fatigue-related car accidents has increased in frequency with fatigued drivers at a higher risk as there is a decline in their driving performance. Thus, a reliable parameter to indicate driver fatigue is crucial. This research aimed to investigate the relationship between three factors: (i) types of roads, (ii) body mass index (BMI), and (iii) gender and their impact on (i) heart rate and (ii) oxygen saturation level (SpO2 ) as indicators of driver fatigue. Methods: A total of 24 experimental runs developed by Design Expert software were conducted on real-road conditions. The investigation was administered during the first 15 minutes and the final 15 minutes of the driving session. Results: Overall, the final 15 minutes of the driving session exhibited a higher heart rate and a lower SpO2 level in comparison to the first 15 minutes. This study discovered a consistent increase in heart rate and a drop in SpO2 level as the driver’s BMI transitioned from the healthy range of 18.5–24.9 kg/m2 to 30 kg/m2 and above, indicating obesity. Also, driving on a monotonous road generated critical driver fatigue compared to relatively demanding urban, uphill/downhill, and winding roads. In addition, female drivers showed higher heart rates and lower SpO2 levels than male drivers during both periods of driving. Conclusion: The current study has established the relationship between types of roads, BMI, gender and their impact on heart rate and SpO2 level. Thus, the outcomes might be useful to academicians and policymakers in the field of road safety in order to prevent traffic accidents due to driver fatigue.