Definition - What does Ultrahazardous Activity mean?
Ultrahazardous activity is any activity or process that is considered so dangerous and potentially harmful that any party or an individual responsible for carrying out the activity becomes “strictly liable” for any injuries or loss caused to others due to that activity.
Justipedia explains Ultrahazardous Activity
Examples of ultrahazardous activities include organizing a professional car race on a busy city street, or working around material that is highly explosive. All such activities will automatically make the organizer strictly liable for any losses that may occur.