You can review this paper: A Public Domain Dataset for Human Activity
Recognition Using Smartphones
In particular, tracking down the references leads to this page containing the "Opportunity" activity data and this specific link to the data.
Instead of the NHTSA FAR data, you may want to look at the NHTSA Vehicle Crash Test Database. This does contain accelerometer data.
That said, I doubt they are using a phone's accelerometer to create this dataset.