Also known as: ultrahazardous · ultra hazardous · ultrahazardous activity · abnormally dangerous
Written by attorneys · grounded in primary & secondary sources — see below
An activity that creates a high degree of risk of serious harm that cannot be eliminated by the exercise of reasonable care. Courts consider factors such as the likelihood and magnitude of harm, the inability to eliminate risk through care, and the appropriateness of the activity to its location when classifying conduct as ultra-hazardous.
Uriah Urban knew the posted warnings and schedule for Upstream Petroleum's blasting operations yet stood near the site to watch. When debris from the blast struck his vehicle, his claim for strict liability failed because he had knowingly and unreasonably exposed himself to the risk.
Ulysses Usher operated a chemical mixing process at Universal Motors that released fumes without intent to harm. The fumes drifted onto Ulrike Ulrich's adjacent greenhouse and damaged her plants, giving rise to private nuisance liability because the release qualified as an abnormally dangerous condition.
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Ulric Unger drove a tanker truck carrying volatile solvents onto Uri Underwood's farm to make a delivery and struck a hidden culvert. The resulting spill contaminated the soil, exposing Ulric to liability because the transport constituted an abnormally dangerous activity that caused the entry.
Usman Uddin parked his delivery van on United Bank's property during a storm when high winds pushed the vehicle across the line. No liability attached for the minor damage because the entry was unintentional and non-negligent and did not involve an abnormally dangerous activity.
Ulysses Maritime stored large quantities of liquefied natural gas in tanks near a residential area. Courts weighed the high risk of explosion, the inability to eliminate that risk through care, and the unsuitability of the location to classify the storage as ultra-hazardous.
Universal Motors kept a tiger on its corporate grounds for promotional events. When a trespasser was injured by the animal, the company's duty of care was measured by the same negligence standard that applies to other artificial conditions rather than a special animal rule.
Courts examine the existence of a high degree of risk, the likelihood that resulting harm will be great, the inability to eliminate the risk through reasonable care, the extent to which the activity is not a matter of common usage, the inappropriateness of the activity to the place where it is carried on, and the extent to which its value to the community is outweighed by its dangerous attributes.
Contributory negligence is not a defense to strict liability for an abnormally dangerous activity unless the plaintiff knowingly and unreasonably subjected himself to the risk of harm from that activity.
An unintentional invasion supports private nuisance liability when the conduct is otherwise actionable under the rules governing liability for abnormally dangerous conditions or activities.
Strict liability is limited to the kind of harm the possibility of which makes the activity abnormally dangerous.
…portion of the rule as set forth in Restatement of Torts, supra : “Except as stated in §§ 521-4, one who carries on an ultra-hazardous activity is liable to another whose person, land or chattels the actor should recognize as likely to be harmed by the unpreventable miscarriage of the activity for harm resulting thereto…