Introduction

In Disaster Management, Hazard, Vulnerability, and Risk are three core concepts. A disaster occurs not only because a hazard exists, but because people and systems are vulnerable to it, creating risk.

Hazard

Definition: A hazard is a potentially damaging physical event, phenomenon, or human activity that may cause loss of life, injury, property damage, social and economic disruption, or environmental degradation.

• Hazards may be natural or man-made. • A hazard does not automatically cause a disaster. • It becomes dangerous when it affects vulnerable people or systems.

Types of Hazards: • Natural: Earthquakes, Floods, Cyclones, Droughts, Landslides. • Man-Made: Industrial Accidents, Chemical Spills, Nuclear Accidents, Fires.

Vulnerability

Definition: Vulnerability refers to the degree to which individuals, communities, or systems are likely to be affected by a hazard due to physical, social, economic, or environmental factors.

• Physical Vulnerability: Weak buildings, poor infrastructure. • Social Vulnerability: Poverty, illiteracy, age (children, elderly). • Economic Vulnerability: Low income, dependence on agriculture. • Environmental Vulnerability: Deforestation, living near rivers.

Risk

Definition: Risk is the probability or likelihood of harmful consequences resulting from the interaction between a hazard and vulnerability.

Risk Formula: Risk = Hazard x Vulnerability

• If either hazard or vulnerability is zero, risk is minimal. • High hazard + high vulnerability = high risk. • Risk can be assessed, managed, and reduced.

Relationship between Hazard, Vulnerability, and Risk

• Hazard: Potentially dangerous event (Usually cannot be reduced). • Vulnerability: Susceptibility to harm (Can be reduced). • Risk: Chance of loss (Can be reduced).

Disaster occurs when a hazard affects a vulnerable population, creating high risk.

Importance

• Helps identify high-risk areas. • Assists in planning and mitigation. • Reduces loss of life and property.