FRAME Calculation examples book. - FRAME Fire Risk Assessment ...

F.R.A.M.E.
site
Fire resistance Structure: 30
Walls: 60
Ceiling: 15
Partitions:0
Escape protection Detection, max. 300,
smoke vents actuated
mixed
concrete
steel
F=1.24
U=3.39
Salvage relocation, data protected Y=2.08
Calculated Risks: R= 1.28 R1= 0.53 R2=0.39
Conclusion:
high level of protection for people and business, higher risk for
property acceptable
A second calculation was made for a 13 000 m² warehouse that was accessible on two sides .
The calculated risks were R= 1.11 R1=0.52 and R2 =0.37 , which shows a comparable risk
level.
A third calculation was made for an undivided warehouse of 21 600 m² with sprinkler
protection instead of smoke detection. The calculated risks were R= 0.98 , R1=0.89 and R2=
0.29 . This gives a better risk, but the cost of the sprinklers was much higher than that of
improving the quality of the existing separations to a firewall type construction.
A fourth calculation was made for a compartment of 4000 m² size, were the plastic pellets
were bagged in PVC bags.
Potential risks were lower as the fire load and the area were smaller :
P = 2.41 P1= 2.02 P2 = 1.46
The values of the acceptable risks indicated a higher exposure , because of the activity :
A = 1.25 A1 = 1.05 A2 = 1.20
The protection degrees were basically the same as the concept was unchanged.
The balance of all elements resulted in the following risk levels :
R= 0.65 R1= 0.73 R2 = 0.36
The concept was considered as adequate for the plant.
Case study 19. Fire safety of a historical building.
The manager of a 13-15 th century monastery, used as museum and cultural centre wanted to
know what the level of fire safety was of this building.
Construction : 2250 m² in a U-shape, 3 levels, very thick stone and masonry walls, wooden
floors, some with tiles, slate roof on massive oak structure. No effective compartimentation
because of two monumental stairs joining the three levels.
The building is accessible on one side only, the other sides are adjacent buildings and a river;
the city water supply is only a 3" pipe; The building is equipped with extinguishers, hose reels,
a fire alarm system and partial fire detection. Notification to the fire brigade is by the staff.
The fire load is low, except for a library with old books, located in the North wing; this library
has a wooden floor and a decorated wooden ceiling, which is also the floor of meeting room at
the upper level. This room can receive about 150 persons and has one adequate and one
limited exit to stairs.
In the central wing, there is a small restaurant and a kitchen.
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