User Manual

Fire Safety
49
Building Technologies 049_Archives_and_Libraries_A6
V10271399_a_en.doc
Fire Safety & Security Products 03.2009
Chart for evaluating extinguishing agents
Extinguishing agents
Secure extin-
guishing
Cools the fire
area
No damages
caused by extin-
guishing agent
H
2
O Gas
  
Gas only
  
Water spray and mist ~

~
Sprinkler system
  
Ratings: yes , somewhat: ~, no: 
Tab. 9 Extinguishing agents evaluation
4.4.4 Extinguishing solutions based on inert gases
Extinguishing with Sinorix N
2
Sinorix N
2
is based on pure nitrogen and offers a
very valid alternative for archives containing
assets that cannot take any water.
When there are additional overpressure restric-
tions in the protected room, Siemens offers
Sinorix CDT N
2
, a unique constant discharge
technology (CDT) that assures minimum
overpressure and turbulences.
Fig. 20 Extinguishing effect of inert gases
Sinorix
TM
N
2
/Ar
Sinorix
TM
technologies based on nitrogen and argon present a good extinguishing
alternative for the protection of archives containing paper, board or organic media.
As already mentioned before the highest efficiency for this types of fires is
achieved with a water combined solution like Sinorix
TM
H
2
O Gas, but Sinorix
TM
N
2
and Sinorix
TM
Ar can also provide the required protection.
When extinguishing deep seated fires with inert agents, the required design con-
centration is relatively high. For example VdS requires for protection of “documen-
tation storage, paintings or similar” a design concentration for argon or nitrogen
of 61% per volume. In such cases the following aspects have to be considered:
1. System: 61% per volume of design concentration requires a big system,
compared to chemical agent solutions. Factors like floor load, size and of
course cost have to be considered
2. Overpressure openings: such volume of gas requires huge overpressure
openings, which represents a challenge in old or historic buildings and also
a cost driver factor.
3. Security for occupants: the remaining oxygen concentration in the room
is very likely to decrease under 10%, posing a potential danger for people
that did not evacuate the room.
When protecting archives containing plastic or electronic media, Sinorix
TM
N
2
and
Sinorix
TM
Ar offer excellent extinguishing results. Here a smoldering fire would be
produced and the required VdS design concentration for this application, is with ni-
trogen 45,2% per volume and with argon 49,1%.