FTA diagram - Hazard analysis

The FTA diagram example "Hazard analysis" was redesigned from the illustration of the article "Hazard Analysis Methodologies" from the Occupational Safety & Health Administration (OSHA) website.
"A fault tree analysis is a quantitative assessment of all of the undesirable outcomes, such as a toxic gas release or explosion, which could result from a specific initiating event. It begins with a graphic representation (using logic symbols) of all possible sequences of events that could result in an incident. The resulting diagram looks like a tree with many branches — each branch listing the sequential events (failures) for different independent paths to the top event. Probabilities (using failure rate data) are assigned to each event and then used to calculate the probability of occurrence of the undesired event. ...
This technique is particularly useful in evaluating the effect of alternative actions on reducing the probability of occurrence of the undesired event."
[osha.gov/ SLTC/ etools/ safetyhealth/ mod4_ tools_ methodologies.html]
The FTA diagram example "Hazard analysis" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Fault Tree Analysis Diagrams solution from the Engineering area of ConceptDraw Solution Park.

This example was redesigned from the Wikimedia Commons file: Example of High Level Fault Tree.jpg. [commons.wikimedia.org/ wiki/ File:Example_ of_ High_ Level_ Fault_ Tree.jpg]
"Risk assessment is the determination of quantitative or qualitative value of risk related to a concrete situation and a recognized threat (also called hazard). Quantitative risk assessment requires calculations of two components of risk (R):, the magnitude of the potential loss (L), and the probability (p) that the loss will occur. Acceptable risk is a risk that is understood and tolerated usually because the cost or difficulty of implementing an effective countermeasure for the associated vulnerability exceeds the expectation of loss.
In all types of engineering of complex systems sophisticated risk assessments are often made within Safety engineering and Reliability engineering when it concerns threats to life, environment or machine functioning. The nuclear, aerospace, oil, rail and military industries have a long history of dealing with risk assessment. Also, medical, hospital, social service and food industries control risks and perform risk assessments on a continual basis. Methods for assessment of risk may differ between industries and whether it pertains to general financial decisions or environmental, ecological, or public health risk assessment." [Risk assessment. Wikipedia]
The FTA diagram example "High level fault tree" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Fault Tree Analysis Diagrams solution from the Engineering area of ConceptDraw Solution Park.