Upload
truonglien
View
224
Download
2
Embed Size (px)
Citation preview
2
Address:Washington street 40B-1050 BrusselsBelgium
[email protected]: +32 2 514 11 71Fax: +32 2 512 90 62
rehvaFederation of European
Heating and Air-conditioning Associations
3
Use of REHVA Guidebook Power Point Presentations
This Power Point Presentation can be freely used for training purposes by REHVA members. It is prepared by the main author of the REHVA Guidebook. Please refer the original author always when making the presentation.Inform REHVA secretariat each time the presentation is used: [email protected]
4
Contents of the book1 In a nutshell: ventilation and
smoking5 National laws and regulations6 Ventilation for the control of ETS7 Passive smoking and health8 Management and interior design of
the premises9 Principles of room air distribution10 Zoning strategies11 Zoning and temperature control12 Ventilation system arrangements
outside the room13 Air cleaners14 Smoking stations15 Smoking rooms16 Design check list
Case studies included in the book:1 Pubs in UK and in Ireland – does
ventilation and/or air cleaners help?2 Restaurant at one level with large
ceiling height3 Multi-storey restaurant4 Smoking zone in a lobby5 Bar and restaurant6 Bar desk with air curtain from below7 Bar area at a ship
6
Purpose of the book
This book describes how ventilation can reduce people’s exposure to environmental tobacco smoke (ETS).
The authors want to emphasise that ventilation cannot give non-smokers total protection against ETS, but by correct ventilation, the exposure can be reduced significantly.
Peaceful coexistence, please.
7
Check list for your project
• Check the national regulations• Apply local exhausts, if possible• Find a good ventilation strategy• Find a suitable layout• Calculate the necessary air volume flow• Check that the detail engineering satisfies the
intentions of your design
.. and Stay with the project until the result is
proven! • Check the air flow patterns.• Find the faults and correct them.• Prove the result!
Experience makes you wise, but not rich.
A project starts…
… and ends.
8
Different countries - different regulationsCheck national and local rules.
FINLAND
NETHERLANDS
SWITZERLAND
ITALY
NORWAY
SWEDEN
0,5μg
18 l/s/m²
22 l/s/pers
Functional requirement
Political requirement
Specified requirement
9
Local exhaust and encapsulation:the best alternative
Inlet velocity > ~ 0,25 m/s
Preferably:close the door
10
Zoning
Ill.:Håkon Skistad
Extract air in the smoking zones
Extract air atthe toilets
Supply air in thenon-smoking zones
Separate ventilationfor the kitchen
Plan the layout of the premises so that smoke contaminated air will not penetrate outside the smoking areas.
11
Zoning
Simply supplying air in one end of a room and extracting in the other end may not be sufficient.
Extract airSupply air
12
Zoning with restriction between the zones
Extract airSupply air Wall with door or opening
The flow velocity between the zones must be great enough to prevent smoke contaminated air flowing back into the non-smoking zone.
13
Zoning with air curtain
An air curtain may be used as restriction between the two zones. But – this requires the right balance between supply air, extract air and the air curtain.
Air curtain
14
Zoning with air curtain
Check that:The supply air flow must be greater than the entrained air flow, qs > qentr
Room air flow must not disturb the air curtain
Keep in mind:An air curtain is not as solid as a physical wall
Non-smoking zone
Smoking zone
Supply airflow,qs
Entrained airflow,
qentr = qs
Extract airflow,qe = qs+qac
Air curtain supply airflow,
qac
15
Zoning with air curtain
Without the right air balance, the air curtain may be just a mix-master in the room air.
16
Zoning with thermal stratification
In multi-storey premises: Arrange the non-smoking zones at the lower floors, and the smoking zones on the floors above. Remember local protection behind the serving counters
Smoking
Non-smoking
17
Local protection
Supplying air behind the serving counters is efficient if the air velocity from inside the counter is great enough, andif there is not much turbulence in the air behind the counter.
18
Local protection
Supply air behind the serving counters. An air curtain may help separating the clean zone from the contaminated zone.
Air curtain
19
Local protection
An air douche may protect a still-standing person.But: This requires a proven supply unit!
Air douche
20
Displacement ventilation?
Hei
ght a
bove
floo
r, z [
m]
Temperature, θ
0
0,5
1,0
1,5
2,0
2,5
Contamination, c room
θroom
θplume 1
θplume 2
croom
Yes, may be…
… but not always.
If the supply air is sufficient for the convection currents, then displacement ventilation is efficient. But if available air flowrates are low, then another principle should be considered.
21
Passive smoking in crowded rooms with Displacement Ventilation
0,0
0,5
1,0
1,5
2,0
2,5
3,0
0 1 2 3 4 5 6
Concentration ratio c/cR
Hei
ght [
m]
Ambient
Exposure, seatedexposure, standing
Source:Peter V- Nielsen, Denmark
A standing person’s exposure may be greater, but people are still protected by the rising air current around themselves
22
Air cleaners
An air cleaner may reduce concentration of dust and gases, but it must only be used together with ventilation of clean air.
qac
cr
Air cleaner
23
Case study: A high class restaurant
A tall room with sufficient air supply: Displacement ventilation gave a good result.
24
Case study: A high class restaurant
Nicotine measurements documentation.
0123456789
10
Method 1 Method 2 Method 3
Nic
otin
e-co
nsen
tratio
n [µ
g/m
³]
Non-smoking
zone
Smokingzone
Lunch11:30 - 15:30
Evening18:00 - 22:00
Action limit10 µg/m³
Reccomended1 µg/m³
Non-smoking
zone
Smokingzone
Smoking zone
Non-sm
oking
zone
Transitionzone
Entrance
Smoking zone
Non-sm
oking
zone
Transitionzone
Entrance
Position for nicotine measurements
25
Case study: A multi-storey restaurant
Smoking
Non-smoking
Nicotine measurements documentation.
0Røyking,øverste
sone
Ikke-røyk,
nederstesone
Serverings-disk,
mellomstenivå
Ikke-røyk,
nederstenivå
5
10
15
20
25
30
Nik
otin
kon
sent
rasj
on [µ
g/m
³]NILU-aktiv RiT-aktiv
Titaksgrense,10 µg/m³
(Røyking forekom en kort stund her)
Grenseverdi1 µg/m³
26
Case study: Smoking area in a lobby:Zoning with air curtains.
Full scale test section at Delft University.
Smoke concentration
Height
uac = 0,75 m/sqac = 2700 m³/h
qe =4500 m³/h
27
Case study: Restaurant with air curtain zoning
670 l/s
890 l/s
300
l/s
Air curtain # 1
610 l/s
Air curtain # 2
Air curtain # 4 Air curtain # 3
400 l/s 150
l/s
150 l/s
750 l/s
610 l/s
Smoking zone,
restaurant
Non-smoking
zone, restaurant
Non-smoking zone, bar
Smoking zone,bar
Diffusers
Air curtains
28
Case study: Bar with air curtain zoning
False ceiling
Supply unit
Air curtain
Protection air
Service area
barcounter