Ventilation

Question 1

What is Ventilation?

Answer 1

The deliberate process of replacing air in a spacpe to maintain air quality. It can be minimised but not eliminated.

Question 2

Ventilation is required to provide air for breathing and mai tain good air equality to remove what?

Answer 2

Indoor air pollutions (odours)
Mold
Volatile organic compounds
Control of excess humidity

Question 3

Name the three different models of Ventilation.

Answer 3

Natural
Mechanical
Mixed mode

Question 4

What can ventilation be measured in?

Answer 4

Litres per second (l/s)
Cubic metres per hour (m³/h)
Air changes per hour (ac/h)

Question 5

What approved document deals with ventilation?

Answer 5

Part F

Question 6

What is Infiltration?

Answer 6

Unplanned leakage

Question 7

How can infiltration occur?

Answer 7

Poor construction

Question 8

New buildings require air leakage test no greater than what?

Answer 8

10m³/m²h @ 50pa (approximately 0.5 ac/h at normal pressure)

Question 9

What is air permeability measured in?

Answer 9

M³/m²h @ 50 pa (pascal)

Question 10

What mph wind speed is 50pa equivalent to?

Answer 10

20mph

Question 11

What does ac/h stand for?

Answer 11

Air changes per hour

Question 12

A very tight envelope means ac/h ranging from what?

Answer 12

0.15 to 0.05

Question 13

What is the requirement for a minimum of 24h avarage air change to avoid the risk of smells?

Answer 13

0.3ac/h

Question 14

How can you achieve Passivhaus standards in the UK?

Answer 14

Accurate design modeling using PHPP

Very high levels of insulation.

Extremely high oerformance windows with insulated frames.

Airtight building fabric.

‘Thermal bridge free’ construction.

A mechanical ventilation system with highly efficient heat recovery.

Question 15

What are the two types of natural ventilations?

Answer 15

Cross ventilation

Stack ventilation

Question 16

What does cross ventilation require and what are the benefits?

Answer 16

Clear path

Good window design

Low cost

Question 17

What does stack ventilation require and what are its benefits?

Answer 17

Good for night time cooling

Low cost

Outside air must be cooler

Clear path

Question 18

Name three different mechanical systems.

Answer 18

Centralised system

Partially centralised

Local systems

Question 19

What is a centralised system?

Answer 19

Where heat, cool and humidity control is done and then ducted around the building.

Question 20

What is a partially centralised system?

Answer 20

A system which adds additional hest and cooling to the air in separate offices.

Question 21

What is a local system?

Answer 21

A system which can be crontolled remotely and turned on and off, such as Air conditioning.

Question 22

What does VAV stand for?

Answer 22

Variable air volume.

Question 23

What does CAV stand for?

Answer 23

Constant air volume.

Question 24

VAV is when?

Answer 24

The temperature of the supply air is constant but the volume varies.

Question 25

CAV is when?

Answer 25

Volume of the supply air is constant but the temperature varies.

Question 26

Which of the two VAV or CAV can you adjust the volume of the air in different parts of the building at different temperatures in?

Answer 26

VAV

Question 27

Expensive to install and maintain, also requires a large area for unit installation.

VAV or CAV

Answer 27

VAV

Question 28

Which of the two requires less space for installation?

VAV or Fan coil system?

Answer 28

Fan coil system as the majority of its work is done through the units in the ceiling.

Question 29

What is another term for localised system?

Answer 29

Split system.

Question 30

What approved document deals with the conservation of fuel and power?

Answer 30

Part L