---
title: "Indoor air pollution and Kathmandu air problems"
subject: "Technology, Environment and Society"
chapter: 5
key: "semester_7/technology_environment_and_society:indoor-air-kathmandu-health"
source: https://www.bctengineer.com/q/semester_7/technology_environment_and_society/indoor-air-kathmandu-health
site: BCT Engineering
---

# Indoor air pollution and Kathmandu air problems

Technology, Environment and Society · Chapter 5: Water and Air Pollution

- Asked in: 2080 Bhadra, 3+5 marks
- Video: [Air Pollution and Its Impact to the People of Kathmandu Report](https://www.youtube.com/watch?v=66Ol4BoXBvE) —  Kathmandu TV
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/technology_environment_and_society/indoor-air-kathmandu-health
- Whole chapter: https://www.bctengineer.com/md/semester_7/technology_environment_and_society/chapter-5

## Question

Define indoor air pollution. Explain the severity of environmental and health problems due to air pollution in Kathmandu.

## Short answer

Indoor air pollution is harmful pollutants indoors from burning solid fuels and kerosene. In Kathmandu, severe air pollution from vehicles, dust, brick kilns, and waste burning, trapped by valley topography, causes respiratory and cardiovascular diseases, reduced lung function, and eye irritation. Environmentally, it creates smog, damages heritage, reduces visibility, and contributes to black carbon deposition on glaciers.

## Answer

#### Indoor air pollution
**Indoor air pollution** is the presence of harmful gases and particles in the air inside buildings (homes, schools, offices). Main sources are burning of firewood, dung, crop waste and kerosene for cooking and heating in poorly ventilated kitchens, tobacco smoke, incense, paints and mould. Key pollutants are PM2.5, carbon monoxide, formaldehyde and NO₂. In Nepal it mainly affects rural women and children, causing pneumonia, COPD, eye disease and low birth weight.

#### Severity of environmental and health problems due to air pollution in Kathmandu
Kathmandu valley is one of the most polluted urban areas of South Asia. Annual average PM2.5 is several times the WHO guideline, and in winter and spring the AQI often reaches the "unhealthy" to "hazardous" range.

**Causes in brief:** vehicle exhaust, road and construction dust, brick kilns, open waste burning, industries, forest fires and trans-boundary haze, made worse by the bowl-shaped valley and winter temperature inversion.

**Health problems**
1. **Respiratory disease** – asthma, bronchitis, COPD and pneumonia; hospitals report more patients in the dry season.
2. **Cardiovascular disease** – PM2.5 enters the blood and increases heart attacks and strokes.
3. **Lung cancer** risk increases with long-term exposure.
4. **Eye, nose and throat irritation**, headache, fatigue.
5. **Vulnerable groups** – children, elderly, pregnant women, traffic police and street vendors are most affected; children's lung growth is reduced.
6. **Lower life expectancy** – studies estimate that air pollution cuts several years of life for valley residents and is a top risk factor for death in Nepal.

**Environmental problems**
1. **Smog and poor visibility** – flights at Tribhuvan International Airport are delayed; mountain views are lost, hurting tourism.
2. **Damage to heritage** – soot and acidic gases blacken and corrode temples, statues and buildings of the World Heritage Sites.
3. **Vegetation damage** – dust on leaves reduces photosynthesis; ozone harms crops.
4. **Climate impact** – black carbon and CO₂ add to warming; black carbon deposited on Himalayan snow speeds melting.
5. **Acid deposition** from SO₂ and NOₓ.
6. **Economic loss** – medical costs, lost work days and reduced tourism.

**Measures:** electric public transport, emission testing, dust control, cleaner brick kilns, ban on open burning, green spaces and air quality monitoring with public warnings.

## Check yourself

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

1. Which best defines indoor air pollution?
   A. Noise levels inside buildings
   B. Harmful gases and particles in the air inside buildings such as homes, schools and offices
   C. Contamination of the water supplied to buildings
   D. Pollutants only in outdoor city air
   Answer: B. It is the presence of harmful gases and particles in indoor air, mainly from burning biomass and kerosene, tobacco smoke, incense, paints and mould. (Key point: Definition of indoor air pollution)

2. Why does PM2.5 increase heart attacks and strokes?
   A. It only irritates the eyes
   B. It stays in the nose and cannot enter the body
   C. It enters the blood
   D. It lowers blood sugar
   Answer: C. Fine particles enter the blood and raise the risk of heart attacks and strokes. (Key point: PM2.5 and cardiovascular harm)

3. Which is an environmental effect of air pollution in Kathmandu mentioned in the answer?
   A. Increased photosynthesis from dust on leaves
   B. Black carbon on Himalayan snow slowing melting
   C. Soot and acidic gases blackening and corroding heritage monuments
   D. Cleaner temples due to acid rain
   Answer: C. Soot and acidic gases blacken and corrode temples and statues; black carbon on snow speeds melting and dust reduces photosynthesis. (Key point: Environmental effects)

## Related in Technology, Environment and Society

- [Severity of indoor air pollution in Nepal](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Aindoor-air-pollution-severity) — Technology, Environment and Society, chapter 5
- [Indoor air pollution in Nepal and counter measures](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Aindoor-air-pollution-nepal) — Technology, Environment and Society, chapter 5
- [Kathmandu air pollution and topography](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Akathmandu-air-topography) — Technology, Environment and Society, chapter 5
- [Kathmandu air pollution and livable city](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Akathmandu-livable-city) — Technology, Environment and Society, chapter 5
- [Kathmandu air pollution: causes, effects, mitigation](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Akathmandu-air-pollution-causes) — Technology, Environment and Society, chapter 5
- [Pollution, onsite sanitation, health education, fecal-oral](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Apollution-sanitation-fecal-oral) — Technology, Environment and Society, chapter 5

## Related in other subjects

- [Health impacts of indoor air pollutants](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Aindoor-air-pollutants-health) — Energy Environment and Society, chapter 4
- [Research article on air pollution in Kathmandu](https://www.bctengineer.com/question.md?key=semester_5%2Fcommunication_english%3Aresearch-article-air-pollution-kathmandu) — Communication English, chapter 10, asked 3×
- [Indoor air pollutants and their sources](https://www.bctengineer.com/question.md?key=semester_7%2Fenvironment_and_pollution_control%3Aindoor-air-pollutants-sources) — Environment and Pollution Control, chapter 3
- [Control strategies for indoor air quality](https://www.bctengineer.com/question.md?key=semester_7%2Fenvironment_and_pollution_control%3Aindoor-air-control-strategies) — Environment and Pollution Control, chapter 3