Indoor Air quality Part 2

Question 1

What is the case study done for indoor air quality?

Answer 1

Monitor quality of indoor air in church in Rome

Question 2

Why is the IAQ monitored?

Answer 2

To assess:
1. Damage to materials in church (art)
2. Acidity in air due to NOs emitted by:
a) industry
b) transportation
c) heating
3. Dry deposition of acidic species/ozone

Question 3

What occurs to the acidic species in the indoor air, give a reaction equation?

Answer 3

Transformed to secondary pollutants:
1. gaseous nitric and nitrous acid
2. acidic sulphates in PM

2 NO2 + H2O -> HONO + HNO3

Question 4

What are the results of the case study?

Answer 4

Indoor levels of NO and HONO exceed outdoor levels

Question 5

What are properties of NO?

Answer 5

1. NO levels higher indoors
2. Outdoor NO higher in the morning
3. Main nitrogen species emitted from combustion process
4. Not removed from atmosphere by dry deposition
5. Rapidly oxidizes, form NO2, nitric acid, nitrate aerosol
6. Removal of NO determined by indoor ozone conc.

Question 5

Why do indoor levels exceed outdoor levels?

Answer 5

1. Once NO and PM transferred indoors
2. Becomes segregated
3. Remain indoors being depleted very slowly due to small deposition velocity

Question 5

What is the reaction producing NO and NO2?

Answer 5

1. N2 + O2 -> 2NO
2. O3 + NO -> NO2

Question 6

Why is the formation of Ozone higher in summer?

Answer 6

Ozone formed by action of sunlight on NO2, in winter not a lot of sun.

Question 6

What is a key parameter in determining indoor conc?

Answer 6

In closed environment: exchange rate

Question 6

How can a pollutant be removed?

Answer 6

On account of its reactivity.