---
title: "Hazard versus risk"
subject: "Engineering Geology II"
chapter: 5
key: "semester_4/engineering_geology_ii:hazard-vs-risk"
source: https://www.bctengineer.com/q/semester_4/engineering_geology_ii/hazard-vs-risk
site: BCT Engineering
---

# Hazard versus risk

Engineering Geology II · Chapter 5: Geological Hazards

- Asked in: 2078 Baisakh, 2 marks; 2075 Baisakh, 3 marks; 2073 Bhadra, 2 marks; 2072 Asoj, 1.5+1.5 marks; 2071 Magh, 2 marks; 2068 Magh, 1 marks (asked 6 times)
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_4/engineering_geology_ii/hazard-vs-risk
- Whole chapter: https://www.bctengineer.com/md/semester_4/engineering_geology_ii/chapter-5

## Question

Differentiate between hazard and risk.

## Short answer

Hazard is a potential damaging event; risk is expected loss = hazard × vulnerability × exposure. Hazard cannot be stopped, but risk can be reduced by lowering vulnerability and exposure. An earthquake in an uninhabited desert is a high hazard but low risk.

## Answer

A **hazard** is a natural or man-made event, process or condition with the potential to cause loss of life, property or environmental damage. **Risk** is the expected loss (probability of harm) from a hazard to the elements exposed, taking account of their vulnerability.

$$
\text{Risk} = \text{Hazard} \times \text{Vulnerability} \times \text{Exposure}
$$

| Point | Hazard | Risk |
|---|---|---|
| Meaning | Source of possible harm | Probability and amount of expected loss |
| Nature | Physical event (landslide, flood) | Combined effect of event and what is exposed |
| Depends on | Magnitude, frequency, location | Hazard, vulnerability, exposure, capacity |
| Can be reduced | Seldom (cannot stop earthquake) | Yes, by lowering vulnerability and exposure |
| Uninhabited area | Hazard may exist | Risk is nil or low |
| Example | A landslide-prone slope | Expected damage to a village below the slope |
| Measure | Probability, intensity | Expected loss (lives, money) |

Example: an earthquake in a desert is a hazard but has little risk; the same earthquake in Kathmandu is a high risk.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is risk?
   A. The probability of rain
   B. Expected loss from a hazard considering vulnerability
   C. The source of possible harm
   D. The event magnitude only
   Answer: B. Risk is expected loss taking account of vulnerability and exposure. (Key point: Risk definition)

2. Which formula gives risk?
   A. Hazard / Exposure
   B. Vulnerability - Hazard
   C. Hazard x Vulnerability x Exposure
   D. Hazard + Vulnerability
   Answer: C. Risk combines hazard, vulnerability and exposure. (Key point: Risk formula)

3. What is the risk of an earthquake in an uninhabited desert?
   A. High
   B. Same as in Kathmandu
   C. Impossible to define hazard
   D. Nil or low, though the hazard exists
   Answer: D. Without exposed people or assets, risk is low even if the hazard exists. (Key point: Uninhabited area)

## Related in Engineering Geology II

- [Define hazard, risk, vulnerability](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Ahazard-risk-vulnerability) — Engineering Geology II, chapter 5, asked 2×

## Related in other subjects

- [Qualitative versus quantitative risk analysis](https://www.bctengineer.com/question.md?key=semester_7%2Fict_project_management%3Aqualitative-vs-quantitative-risk) — ICT Project Management, chapter 12