Accident

In recent years worldwide, the most common causes of accidental deaths have been road traffic incidents and falls. Writing of accidental deaths, one author says the "vast majority of accidents are not really accidents of chance, but rather accidents of folly, negligence, and blatant human misjudgment", with research showing that up to 80% of events that are called accidents are caused by human error. Many different theoretical models have been proposed for analyzing accidents, but no single model has yet proved sufficient for these often-complex events.

Types

Physical and non-physical

Physical examples of accidents include unintended motor vehicle collisions, malfunctioning machinery, drowning, falling, or unintentional contact with something sharp or hot or electrified or poisonous (including drug overdoses). Unintended pregnancies and unintended scientific discoveries are also sometimes described as accidental.

Non-physical examples include unintentionally revealing a secret or otherwise saying something incorrectly, or forgetting an appointment.

Work and leisure

Accidents during the course of work, or arising out of it, are called work accidents, occupational accidents, or similar terms. According to the International Labour Organization, approximately 400 million accidents happen on the job each year (5% of the world population), causing more than 300,000 deaths annually (especially in mining and construction) and millions of long-term disabilities (especially back injuries).

In contrast, leisure-related accidents are mainly sports injuries, with lower fatality rates.

In process manufacturing, a primary accident (such as leakage, fire or explosion) may propagate to nearby units, resulting in an escalating chain of failure, which is often called a domino effect accident.

Commercial products sometimes emerge from accidental discoveries, famously including penicillin, Post-it notes, and microwave ovens. Injuries that occur during travel to or from employment are sometimes counted statistically as work accidents, but are usually classified separately as transportation accidents instead.

Transportation

Aviation

Aviation safety has improved dramatically through decades of concerted effort. Although individual crashes can have high fatality counts and widespread publicity, modern air travel has approximately just 1 fatal crash per 16 million commercial flights (as of 2024), or 1 death per 35 billion passenger-kilometers (22 billion miles), far better than historical rates, and generally the safest way to travel a given distance over land. Airplane accidents occur most commonly during the landing process.

Bicycles and motorcycles

Unenclosed two-wheel vehicles are more economical but less visible than the much larger cars and trucks on the road, and bikes offer their riders little protection from collision or weather or hazardous road conditions. For these reasons, bicycle or motorcycle travel typically has multiple times the risk of car travel over a given distance. Electric bikes present the further risk of accidental fire from the overheating of their powerful batteries, especially from lower-quality manufacturers.

Maritime

Water transportation accidents are far too diverse for any simple generalization or statistic. Modern mega-cruise ships are akin to slow-motion cities, where accidental deaths are dwarfed by ordinary heart attacks and strokes. At the opposite extreme of size, technology, and regulation, refugee boats and whitewater kayaks are much riskier than luxury cruise ships. Ferries overloaded with impoverished crowds capsize regularly, and so do the sailboats of wealthy adventurers, and cargo ships in hazardous waters. Any attempt to summarize maritime accidents would need to recognize all these differences and more.

Road traffic

Most vehicle collisions are triggered by preventable driver behaviors such as drunk, drowsy, distracted, or dangerously fast driving, and are not true accidents in the strictest sense. The use of the word accident to describe car wrecks was promoted by the US National Automobile Chamber of Commerce in the middle of the 20th century, as a way to make vehicle-related deaths and injuries seem like an unavoidable matter of fate, rather than a problem that could be addressed by automotive safety. The automobile industry accomplished this by writing customized articles about local collisions as a free service for newspapers that used the industry's preferred language. Since 1994, the US National Highway Traffic Safety Administration has asked media and the public not to use the word accident to describe vehicle collisions.

Trains

For a given distance, passenger trains (and also buses) are considerably safer than car traffic, although riskier than commercial aircraft. Major rail accidents can also arise from freight trains, carrying bulk quantities of hazardous cargo but few people. Unlike most other transportation accidents, a large fraction of train casualties are people out along the route, not riding on the train itself.