There are really two parts to a good accident analysis:
1. Monitoring the frequency of accidents over time, which is a measure of the effectiveness of the safety program.
2. Monitoring the types and severity of accidents.
First, you should monitor the frequency of accidents. Accidents should be classified as either preventable or non-preventable, and whether the accident was DOT recordable. Frequency rates can be calculated for any period of time (e.g., quarterly or annually). Separate rates can be calculated for:
- Overall frequency rate (all accidents, regardless of severity or preventability).
- DOT recordable rate (only accidents that were DOT recordable).
- DOT recordable/preventable rate (only accidents that were both DOT recordable and preventable on the part of the driver).
To calculate the rate for any period, you simply need to know the number of accidents for that period, and the total miles traveled for the same period. The formula is shown to the left. These rates, if tracked, can help monitor the long-term results of your safety and loss control program.