Also known as: ultrahazardous activity · ultra hazardous activity · ultrahazardous activities · abnormally dangerous activity
Written by attorneys · grounded in primary & secondary sources — see below
An activity so inherently dangerous that one who carries it on is subject to strict liability for resulting harm even if the utmost care is exercised. The doctrine places the loss on the actor who chooses to engage in the activity rather than on innocent victims. Contributory negligence does not bar recovery unless the plaintiff voluntarily and unreasonably assumes the risk.
Uri Underwood operates a quarry and detonates explosives to clear rock. Neighboring farmer Ursula Ung leaves her tractor parked close to the blast site despite posted warnings and suffers damage when debris strikes it. Ursula's decision to park nearby does not bar recovery because contributory negligence is not a defense to strict liability for the abnormally dangerous activity.
Umbra Technologies conducts pressurized tank testing at its chemical plant. A relief valve fails during an uninspected cycle and releases corrosive vapor that crosses onto the adjacent lot owned by Ulysses Ulrich, pitting his metal equipment. The entry caused by the abnormally dangerous activity subjects Umbra to liability even though the vapor crossed unintentionally.
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Unity Capital's crane operator follows all standard protocols while lifting a steel beam on a high-rise project. An unforecast gust swings the beam across the property line onto Gate Development's condominium, cracking stone panels. Because the lift is not an abnormally dangerous activity the unintentional non-negligent entry does not create liability.
Foster operates a logging mill that uses explosives to remove stumps. The blasts frighten mink on a nearby farm owned by Preston, causing the animals to kill their young. Strict liability is limited to harm that flows from the extraordinary risk that makes the activity ultra-hazardous, so Foster is not liable for the indirect loss.
Omega Flex manufactures flexible gas piping installed in Tincher's home. A lightning strike causes the pipe to fail and release gas that ignites. The court applies strict liability principles to determine whether the product's design created an abnormally dangerous condition that warrants liability without fault.
Consolidated Rail stores chemicals near People Express Airlines' terminal. A leak forces evacuation and shuts down operations, causing the airline substantial lost profits. The court examines whether the abnormally dangerous activity creates liability for purely economic harm to nearby businesses.
No. The plaintiff's contributory negligence is not a defense to strict liability for one who carries on an abnormally dangerous activity unless the plaintiff voluntarily and unreasonably assumes the risk.
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An unintentional and non-negligent entry does not create liability unless the actor is engaged in an abnormally dangerous activity. The exception removes the usual protection for accidental entries when the activity itself is ultra-hazardous.
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Liability is confined to harm that results from the extraordinary risk that makes the activity ultra-hazardous. Harm outside that risk does not trigger strict liability even if it occurs during the activity.
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Courts examine whether the activity creates a foreseeable risk of economic harm to nearby businesses. Recovery may be allowed when the harm is a direct consequence of the dangerous character of the activity.
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…for example, upon keepers of wild animals, or those who handled explosives or other dangerous substances, or who engaged in ultrahazardous activities. Simultaneously, and more particularly, those who were injured in the use of personal property were permitted recovery on a contract theory if they were the purchasers of the chattel or…