Hazard Analysis Flashcards

A 'common cause failure' in hazard analysis refers to:

Answer: A single event or root cause that simultaneously defeats multiple independent safety barriers

Common cause failure (CCF) describes a situation where a single shared root cause defeats multiple supposedly independent redundant elements or safety barriers at the same time.

A test conductor is reviewing a new explosive ordnance test. Which hazard analysis should be completed FIRST in the safety process?

Answer: Preliminary Hazard Analysis (PHA)

The Preliminary Hazard Analysis (PHA) is the first hazard analysis performed, conducted early in the concept or design phase to identify initial hazards before detailed system design is established.

Quantitative risk assessment differs from qualitative risk assessment primarily in that quantitative methods:

Answer: Assign numerical probability values and calculate expected losses

Quantitative risk assessment uses actual numerical probabilities and consequence values (e.g., expected fatalities per flight hour) whereas qualitative methods use descriptive categories like 'frequent' or 'critical.'

In bow-tie analysis, what does the 'tie' (or node) at the center of the diagram represent?

Answer: The critical event or top hazard that the analysis centers on

In a bow-tie diagram, the knot at the center represents the critical event (hazard realization), with threats and barriers on the left (prevention) and consequences and recovery controls on the right.

A test item is found to have an unacceptable risk level. The test conductor must choose between delaying the test to implement new engineering controls or proceeding with additional administrative controls. According to the hazard control hierarchy, the correct approach is to:

Answer: Apply engineering controls first as they are higher in the control hierarchy

The hierarchy of controls (elimination → substitution → engineering → administrative → PPE) requires that higher-order controls be preferred over lower-order ones; engineering controls must be prioritized over administrative controls.

Which term describes the minimum safe distance that must be maintained between a potentially hazardous item and exposed personnel during testing?

Answer: Minimum Separation Distance (MSD) or Quantity Distance (QD)

Minimum Separation Distance (MSD) or Quantity Distance (QD) defines the minimum distance between a hazardous quantity of material (e.g., explosives) and personnel or structures to reduce risk to acceptable levels.

A 'mishap probability' in MIL-STD-882 terminology refers to:

Answer: The likelihood that the hazard will result in a mishap given the exposure and existing controls

Mishap probability in MIL-STD-882 is the likelihood that a hazard will result in a mishap (loss event) within the system's life cycle, given the operational environment and controls in place.