Fire safety engineering methodology Heinz Reimann Senior Engineer Bombardier Transportation > EC TRANSFEU Project > Final Conference Hotel Marivaux, Brussels 25th September 2012
Fire safety
engineering
methodology
Heinz Reimann
Senior Engineer
Bombardier Transportation
> EC TRANSFEU Project
> Final Conference
Hotel Marivaux, Brussels
25th September 2012
Fire safety engineering methodology
Content
Introduction
Definitions
Presentation of general Fire safety
engineering (FSE) methodology
Fire safety objectives and performance
criteria
Methods and tools for fire performance
and passenger evacuation
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Fire safety engineering methodology
Introduction
Transfeu is using for fire safety engineering International
and European Standards where applicable.
Transfeu development results shall guide future Standard
development
The definition of Fire safety engineering according
ISO 13943;2000 is the following:
Application of engineering methods based on
scientific principles to the development or
assessment of designs in the built environment
through the analysis of specific fire scenarios or
through the quantification of risk for a group of fire
scenarios
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Fire safety engineering methodology
Definitions
RSET Time required for escape
The term RSET is defined in Definition in (ISO13571, 2007) as
“Calculated time required for occupants to travel from their
location at the time of ignition to a place of safe refuge”.
Definition for use of Transfeu
Estimated time required for passenger and staff to escape
from their location at time of ignition to a safe area in the
train.
Note : Transfeu do not consider the safety of passenger in the
safe refuge. (Safe area outside a train.)
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Fire safety engineering methodology
Definitions (continue)
ASET Available safe escape time
Definition according (ISO13571, 2007)
For an individual occupant, the calculated time interval
between the time of ignition and the time at which conditions
become such that the occupant is estimated to be
incapacitated, i.e. unable to take effective action to escape to
a safe refuge or place of safety.
NOTE 1 The time of ignition may be known, e.g. in the case of a fire model or a fire test, or it
may be assumed, e.g. it may be based upon an estimate working back from the time of
detection. It is necessary to state the basis on which the time of ignition is determined.
NOTE 2 This definition equates incapacitation with failure to escape. Other criteria for ASET
are possible. It is necessary to state if an alternative criterion is selected.
NOTE 3 Each occupant may have a different value of ASET, depending on that occupant’s
personal characteristic
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Fire safety engineering methodology
Definitions (continue)
Safe area outside a train
A safe area outside a train is a survivable space, inside or
outside the tunnel, for passengers and staff to find refuge after
they have evacuated from a train.
A passenger station (in a tunnel or at the surface) can be a
safe area if it meets the requirements of paragraph 4.2.1.5. of
TSI SRT.
Note: Definition out of the revision of TSI SRT V2.0
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Fire safety engineering methodology
Definitions (continue)
Safe area in the train
A safe area in a Train for passengers and staff area is the
passenger’s area on board a train of operation category B,
where the passengers and or the staff have shelter from the
immediate effects of a fire, such as heat exposure, smoke
opacity and toxic gases during a minimum time of 15 minutes.
Note: Protected by fire barriers according (prEN 45545-3,
2012) with the IE test criteria’s. The effects of smoke transfer
are considered minimal if the integrity requirements of (prEN
45545-3, 2012) are respected.
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Fire safety engineering methodology
General methodology for FSE
● Definition of fire safety objective and associatedcriteria of performance and acceptance
● Fire risk analysis and design fire scenarios
● Choice of numerical simulation tools for theevaluation of fire performance
● Input data to use in the numerical simulation tools
Fire safety engineering methodology
Fire safety objectives
The fire safety objectives are identical for Passenger Railway
vehicles, Passenger buses and Passenger ships.
The performance criteria’s are different according the different
hazards.
The following objectives shall be taken in account:
Prevent occurrence of fire
Protect passenger and staff in the event of a fire on
board
Provide means of escape for passenger and staff
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Fire safety engineering methodology
Fire safety performance criteria
For technical areas in Passenger ships
The following areas are considered as technical areas:
Cabinets for Electrical -, Control - and Auxiliary equipment
Diesel engine area.
These technical areas shall be protected with fire barrier having
a separation. The following requirements are for duration of 60
minutes according to EN 1363-1 and the heat curve of ISO 834.
E Integrity
I Insulation
S Smoke leakage (Preventing smoke passage)
The diesel engine area shall be protected with a fire fighting
system
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Fire safety engineering methodology
Fire safety performance criteria
Fire effluents which reduces the mobility for evacuation
Heat exposure
For evacuation of the passenger and staff, the heat exposure
anywhere on the evacuation path out of the danger zone shall
not be bigger than as a heat dose max 60 kJ/m2 over the energy
from heat flux level of 1 kW/m2; heat flux max 2.5 kW/m2
Reference: (The Swedish National Board of Housing, Building
and Planning – BOVERKET: Guidance on performance-based
design of buildings (2011))
Temperature exposure
For evacuation of the passenger and staff, the maximal
temperature in the evacuation environment shall be 80 °C.
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Fire safety engineering methodology
Fire safety performance criteria
Fire effluents which reduces the mobility for evacuation
Smoke optical density
During evacuation time out of the danger zone the passenger
and staff in passenger vehicles and ships shall have visibility of
the escape route of a length of 16 m within a height of 1.5 m.
In passenger buses the visibility of the escape route of a length
of 5 m within a height of 1,5 m from the floor level.
For passenger ships the escape ways shall be guided in
accordance with ISO 15370
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Fire safety engineering methodology
Fire safety performance criteria
Fire effluents which reduces the mobility for evacuation
Toxic effect of fire gasesUsing the FED/FEC concept described in ISO 13571 provides a calculation
method for estimating the time available for occupants to escape from a fire
(i.e. ASET). The method examines both the asphyxiant effect (based on an
FED calculation) and the irritant effect (based on an FEC calculation) of fire
gases. The time available for escape depends on which effect is predicted to
occur first.
Estimation of the minimum required ASET Railway vehicles Operation category 1 4.5 Minutes
Railway vehicles Operation category 2,3 7.5 Minutes
Railway vehicles Operation category 4 20 Minutes
Passenger buses 4.5 Minutes
Passenger ships 20 Minutes
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Fire safety engineering methodology
Fire risk analysis and Design Fire Scenario
Risk analysisbased on the following investigations:Analysis of accidental fires with regard to ignition sources, type,
intensity and location.Identification of fire hazards (different procedures will be used to
identify the hazards; HAZOP, PHA, FMEA etc.)
Design fire scenariowill take into account:Vehicle geometry (train, ship, bus), ventilation, passive fire protection (reaction to fire performance of materials
and products) fire resistance of structures, escape routes active fire prevention (detection, smoke extraction, extinguishing).
will define the design fire
Fire safety engineering methodology
Result of the fire risk analyse
Fire safety engineering methodology
Design fire scenario
● Scenario 2A and 2B
● Scenario 1 A and 1B
Fire safety engineering methodology
Fire ignition source
Ignition source for the passenger area for
Railway vehicles and ShipsThe maximum ignition source of interiors is a piece of burning luggage and
this can be considered equivalent to model 5 described in Annex A of
prEN 45545-1. (75kW during 2 minutes and 150KW during 8 minutes)
This luggage can be placed by accident in front of or above a seat. A 100 g
UIC 564-2 – paper cushion (newspapers) is of equivalent effect to primary
ignition.
This ignition source is identical with the design fire for full-scale and real-scale
test and was validated during the risk analyse in Task 4.2
Note: Any volume used for the placement of luggage in accordance with the
operational protocol which is less than 0,55m x 0,35m x 0,25m in any
orientation shall not be considered as a location of a burning luggage
(model 5 ignition source).
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Fire safety engineering methodology
Fire ignition source
Ignition source for technical areas for Railway vehicles
●Technical areas with High voltage circuits, which are directly
linked with the catenary line and those containing Diesel
engines are protected with fire barriers and the ignition source
is considered to be equivalent to model 5 described in Annex
A of pr EN 45545-1.
(75kW during 2 minutes and 150KW during 8 minutes).
●Technical areas with electrical circuits which are electrically
protected, the ignition source is considered to be equivalent to
model 2 according Annex A of pr EN 45545-1
(A radiant flux of nominal value 25 kWm-2 applied to an area
of 0,1 m2.)
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Fire safety engineering methodology
Fire ignition source
Ignition source for the passenger area for buses
The primary ignition source should be equal to a paper cushion
and similar to the ignition source 1 as defined in Annex A of pr
EN 45545.
There is no possibility of starting a fire from luggage in the
passenger area; luggage shall be placed in a special luggage
compartment.
Ignition source for technical area for buses
For diesel engines placed in the engine bay model 5 according
Annex A of pr EN 45545-1is applicable.
(75kW during 2 minutes and 150KW during 8 minutes)19
Fire safety engineering methodology
Methods and tools for fire performance
and passenger evacuation
Introduction and objectives
Existing numerical simulations tools are principally developed
for building applications but surface transport investigations do
pose specific implications with regard to the influence of
different parameters on the fire and smoke development.
This is why adapted simulation tools will be developed in the
WP5, which will be validated by tests on real trains in the
WP6.
However, many conditions which are considered in the train
are similar for other surface transportation vehicles.
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Fire safety engineering methodology
Numerical simulation tools for a FSE study
Calculation tools, to evaluate the following performances:
Fire growth, smoke movements (FDS)
Thermal transfer, heat fluxes
Structural behaviour in case of fire
Atmospheric dispersion
Simulation of product reaction or resistance to fire
Toxicity effect
Fire safety engineering methodology
Methods and tools for fire performance
and passenger evacuation
Simulation tool of fire effluents
Transfeu partners agreed to work with computer codes
designed for fire:
A general fire modelling code, Fire Dynamics Simulator (FDS)
version 5.5, developed in partnership between NIST (USA)
and VTT (Transfeu partner).
Simulation tool for passenger evacuation
We decided to use FDS + Evac, because it is inside fire
simulation model FDS, which is used for trains in TRANSFEU
project.
Tool for assessing fire barriers during design
Assessment of fire barrier design with cone-calorimeter test
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Fire safety engineering methodology
Development plan for the use the FDS for Fire
safety engineering
Request for Transfeu
The project was to develop new simulation tools for trains in
order to predict the ASET (Available Safe Escape Time) in
simulating the different following effects on passenger and
staff:
Visibility (due to smoke)
Incapacitation (due to toxic gas)
Tenability (Temperature, radiation)
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Fire safety engineering methodology
Development plan for the use the FDS for Fire
safety engineering
Three methods have been developed in order to model the fire
source from the simplest one (prescribed source method to the
most complex one (calculated pyrolysis rate method).
Method 1 Simply yield (Prescribed HRR and burnt area)
Method 2 Kinetic yield (Prescribed HRR and thermal properties)
Method 3 Detailed yield (Pyrolysis calculated)
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Fire safety engineering methodology
Input data for validation of
the numerical simulation tools
Types of data:
Thermal physical and chemical data
Resistance and reaction to fire small scale tests
Full & Real scale tests for validation of the
numerical simulation tools using the
Thermal, physical and chemical data;
small scale test results.
Fire safety engineering methodology
Reaction to fire Small scale tests
Heat release Spread of flame
Opacity of smoke
+ FTIR Gas cell
ISO 5660-1 ISO 5658-2
ISO 5659-2
FTIR Gas cell++
Fire safety engineering methodology
Large & real experiments for validation of the
numerical simulation tools Small Scale fire
Tests on material
Real scale Fire test
on product in
vehicle
Small scale fire
models
Full scale fire
test on product
Full scale fire
models
Fire growth, smoke movements
models in vehicle
validation
validation
Pyrolysis Inputs
ISO 5660-1
Fire safety engineering methodology
The use of Simulation tools for
Fire safety engineering
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Transfeu Task Validation results with full & real scale tests
Use for fire safety engineering
Develop new simulation tools for trains taken into account in order to predict the ASET (Available Safe Escape Time) in simulating the different following effects on passenger and staff:
Visibility (due to smoke)
Incapacitation (due to toxic gas)
Tenability (Temperature, radiation)
For the multi-scale methodology
The validation of Full scale and Real scale test are in progress.
The simulation of production of opaque smoke needs additional investigations.
The model of the ignition source with different heat density zones shall be done more intensive to predict the burnt area of the impacted combustible material
It seems that the use of model 1 have finally the most benefit for simulation of the complete passenger area. The model 2 and 3 can be used for detail study Additional consideration will be made during FDS simulation that the burned area taken in account in a realistic way.
Fire safety engineering methodology
The use of Simulation tools for
Fire safety engineering
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Transfeu Task Validation results with full & real scale tests
Use for fire safety engineering
Completed FDS + EVAC tool for passenger evacuation in Railway vehicles
Validation of the different scenario according the actual knowledge was successful
The simulation tool was used to calculate the minimum requested time for ASET
FDS tool for the assessment of fire barrier during design with the cone calorimeter
The simulation results using Cone-calorimeter results were validated with medium size furnaces successful.
Furthermore, cone calorimeter experiments together with FDS simulations can be used to define real scale fire separating performance for assumed fire exposures.
Fire safety engineering methodology
Thank You very much for Your attention !
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