The complicated mechanism is explained in

Dissipation
As the RFD completely wraps around and chokes off the tornados air supply, the vortex begins to weaken, becoming thin and rope-like. This is the "dissipating stage", often lasting no more than a few minutes, after which the tornado ends. During this stage, the shape of the tornado becomes highly influenced by the winds of the parent storm, and can be blown into fantastic patterns. Even though the tornado is dissipating, it is still capable of causing damage. The storm is contracting into a rope-like tube and, due to conservation of angular momentum, winds can increase at this point.As the tornado enters the dissipating stage, its associated mesocyclone often weakens as well, as the rear flank downdraft cuts off the inflow powering it. Sometimes, in intense supercells, tornadoes can develop cyclically. As the first mesocyclone and associated tornado dissipate, the storms inflow may be concentrated into a new area closer to the center of the storm and possibly feed a new mesocyclone. If a new mesocyclone develops, the cycle may start again, producing one or more new tornadoes. Occasionally, the old (occluded) mesocyclone and the new mesocyclone produce a tornado at the same time.Although this is a widely accepted theory for how most tornadoes form, live, and die, it does not explain the formation of smaller tornadoes, such as landspouts, long-lived tornadoes, or tornadoes with multiple vortices. These each have different mechanisms which influence their development—however, most tornadoes follow a pattern similar to this one.
Accident models
Many models to characterize and analyze accidents have been proposed, which can be classified by type. No single model is the sole correct approach. Notable types and models include:
Sequential models
Domino Theory
Loss Causation Model
Complex linear models
Energy Damage Model
Time sequence models
Generalized Time Sequence Model
Accident Evolution and Barrier Function
Epidemiological models
Gordon 1949
Onward Mappings Model based on Resident Pathogens Metaphor
Process model
Benner 1975
Systemic models
Rasmussen
Reason Model of System Safety (embedding the Swiss cheese model)
Healthcare error proliferation model
Human reliability
Woods, 1994
Non-linear models
System accident
Systems-Theoretic Accident Model and Process (STAMP)
Functional Resonance Analysis Method (FRAM)
Assertions that all existing models are insufficientIshikawa diagrams are sometimes used to illustrate root-cause analysis and five whys discussions. See also
General
Accident analysis
Root cause analysis
Accident-proneness
Idiot-proof
Injury
Injury prevention
List of accidents and disasters by death toll
Safety
Safety engineering
Fail-safe
Poka-yoke
Risk management

Transportation
Air safety
Aviation accidents and incidents
Bicycle safety
Car
Automobile safety
Traffic collision
List of rail accidents
Tram accident
Sailing ship accidents

Other specific topics
Aisles: Safety and regulatory considerations
Explosives safety
Nuclear and radiation accidents
Occupational safety and health
Safety data sheet
Personal protective equipment
Criticality accident
Sports injury

References


== External links ==