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Monica Capobelli, PE

Chiara Crosti, PhD, PE

Konstantinos Gkoumas, PhD, PE

Il comportamento umano da comparsa a

protagonista: modellazione dell’evacuazione

di un capannone industriale

VALUTAZIONE E GESTIONE

DEL RISCHIO NEGLI INSEDIAMENTI

CIVILI ED INDUSTRIALI

VGR 2016

Roma, 13 - 15 Settembre 2016

Istituto Superiore Antincendi

Via del Commercio, 13

14/09/2016Il comportamento umano da comparsa a protagonista:

modellazione dell’evacuazione di un capannone industriale

December 31 2015

The Address Downtown Dubai Hotel

15 injured

1 dead

heart attack from the smoke and over-

crowding during an evacuation

1/2514/09/2016Il comportamento umano da comparsa a protagonista:


April 26 2013

Psychiatric hospital – Dmitrovsky

district (Moscow)

2:00 development of fire

38 dead: 36 patients and 2

healthcare assistants

3 survivors


modellazione dell’evacuazione di un capannone industriale 2/25

NUOVO CODICE DI PREVENZIONE INCENDI

D.M

03/08/2015

“Approvazione di norme tecniche di prevenzione incendi, ai sensi

dell’articolo 15 del decreto legislative 8 marzo 2006, n. 139”

OBIETTIVI Disporre di un testo unico

Semplificare

Adottare regole meno prescrittive, più prestazionali e flessibili

Prevedere la possibilità di scegliere fra diverse soluzioni

Favorire l’utilizzo dell’ingegneria antincendio



ASET VS RSET

BASIC PRINCIPLE ASET > RSET

RSET : Required safe escape time

ASET : Available safe escape time by a fire model or similar tools

𝒕𝑹𝑺𝑬𝑻 = ∆𝒕𝑫𝑬𝑻 + ∆𝒕𝑨 + (∆𝒕𝑷𝑹𝑬 + ∆𝒕𝑻𝑹𝑨𝑽)

MILLING



HUMAN BEHAVIOR IN FIRE

Human behavior in fire:

how people respond to several cues

Awareness

Beliefs

Attitudes

Motivations

Decisions

Behaviors

Coping strategiesStudy of human

behavior in fire

Engineering

Architecture

Computer Science

Mathematics

Law

Sociology

Psychology

Human Factors

Communications

Ergonomics

COMPLEXITY

• Many situations cannot be

simulated in laboratory

• Data, extracted from drills

without surprise, stress and

panic, are not very reliable

• It is typically not permitted to

deliberately expose participants

to real fire conditions



LITERATURE REVIEW

The pre-recognition years from the 1900s to the 1970s

1909: design of the Hudson Terminal Building

1927: first edition of Building Code (NFPA)

1935: “Post-War Building studies, No. 29” (Great Britain)

1955: Togawa found an equation for the “time required to escape”

1956: John Bryan investigated the Arundel Park fire incident and verified

a reentry behavior by members of family groups

1969: Pauls started long term studies and observations of many evacuation drills in

tall buildings.The developed “drill” method became one of the key methods for

studying the evacuation behavior

1972: Wood analyzed the behavior of more than 2000 people in nearly 1000 fires

Behavior of male in emergency was different from females

The studies of human

behavior in fire

The pre-recognition years (Exploration of the key topics)

The productive years (Rapid development)

The Performance Code incentive years

(The interpretation of fire safety of building changes)



LITERATURE REVIEW

1973: report of the national commission on fire prevention and control entitled

«America Burning». Included human behavior primarily to the educational aspects of

fire prevention

1972-1982: National Research Council of Canada conducted many observations

that examined people’s movement

1975: First International meeting at NBS

1975: J. Keating and E. Lotus from the University of Washington published «People

care in fire emergency-psychological aspects

1978:“Planning for Foot Traffic Flow in buildings” by Predtechenkii and Milinskii

1979: Bryan and Di Nenno studied the apartment fire in Georgia and they identified

the «clustering phenomenon»

During the 1970s and 1980s, the National Bureau of Standards (NBS) through the

Center for Fire Research, was the primary source for funding human behavior in fire

studies in the United States

1980: National Conference on fire and life safety for the handicapped at Howard

University in Washington D.C.

1985: 1st International Symposium on Fire Safety Engineering

The productive years of the 1970s and 1980s

:



LITERATURE REVIEW

The Performance Code incentive years from the 1990s into

the 2000s 1993: explosion incident of the WTC. One of the most intensively

studied evacuations

1996/1997: Fahy developed her evacuation model (EXIT 89)

1998: 1th International Symposium on Human Behavior in

fire in Belfast

2001: more studies were started after the twin towers collapsed

2001: Sime introduced an Occupant Response Shelter Escape Time

(ORSET) model



FIRE RESPONSE PERFORMANCE

Individual’s ability to perceive and interpret signs of danger, and make and carry out

decision aimed at surviving a fire.



FIRE RESPONSE PERFORMANCE

• Individual features

• Social features

• Situational features

HUMAN

FEATURES

Gender, age, personality traits

Physical and sensory capabilities,

role/responsibility, social affiliation,

commitmentAwareness, position, familiarity

BUILDING

FEATURES

• Situational features

• Engineered features

Occupation density, focal point,

presence of a Building Evacuation

Team (BET)

Complex space, escape route signage,

the design of the escape route

FIRE

FEATURES

• Perceptual features

• Fire growth rate

• Smoke yield and toxicity

(SFPE 5th

edition)



BEHAVIORAL PROCESS

PHASE 1: Perception of the cue(s)

PHASE 2: Interpretation of the cue,

situation and risk

PHASE 3: Decision-making

PHASE 4: Actions

WAYFINDING Process in which the occupant attempts to find a path that leads

him to relative safety

Individuation of wayfinding

criteria

Development of wayfinding

algorithms used within

evacuation models

Simulation more real

(NIST Technical note 1619)



Affiliative

behavior

Convergence

cluster

Re-entry

behavior

Assistance

behavior

Occupant firefighting

behavior

The family

members were

more likely to

maintain group

ties during

evacuation

The clusters

involve

occupants

converging in

specific rooms

they perceived

as areas of

refuges

The occupant

chooses to re-

enter the

building. The

reentry

participants

are mostly

male

Able-bodied

occupants

help other

occupant

that are not

as able-

bodied

This response appears

most prevalent in

buildings in which the

individuals are

emotionally or

economically involved or

where they were trained

or assigned to this role

OCCUPANT BEHAVIOR DURING FIRE EMERGENCY

Influence the Ttrav

Disabilities manifest themselves in varying

degrees

The emergency can cause temporary disability

To consider that the occupants with

movement disability often use special devices

Strategies

Evacuation elevators

Refuge areas

DISABLED IN FIRE EMERGENCY



THE STUDY OF HUMAN BEHAVIOR

Difficult to study

FIRE DRILLS

• An appropriate approach

• Without stress, anxiety, fear and panic

conditions

NUMERICAL SIMULATIONS

• An alternative method to simulate several

scenarios considering the occupants’

characteristics without damaging the

human safety

http://virtual.vtt.fi/

virtual/proj6/fdseva

c/examples_fds6.ht

ml



MAIN FEATURES OF EGRESS MODELS

MODELS AVAILABLE TO THE PUBLIC (NIST Technical Note 1680)



FDSFIRE AND EVACUATION SIMULATION

Evac Fire modelling

Computational Fluid Dynamics (CFD)

model

Geometry modelled with a three

dimensional mesh of volumes control and

their dimension is chosen by the user

Resolves conservation equations (mass,

momentum, energy)

Finite volume method

Evacuation modeling

Multi-agent model

Five body types:

Adult, Male, Female, Child and Elderly

Agent movement algorithm:

method of Helbing’s group = social force

Four agent types:

Conservative, Active, Herding, Follower

each agent is

represented

by three

circles

+



CASE STUDY

A

Comp. SX Comp. DX

D

Activity n°36 D.P.R 151/2011

• 20𝑚 × 75𝑚• ℎ = 5 ÷ 7• Wood storage

• Area of openings = Af (plan area, fire load)

each compartment

• 3,3m long 1m high

• 20 ribbon windows on the two exterior sides

of the building.

𝐴𝑓 = ൗ1 25𝐴 = 60𝑚2

Fire load• Wooden pallet => H=17,5 MJ/m2

• Europallet 1,2x0,8x0,145m

• Weight = 25 kg

• 15500 for each compartment

𝑞𝑓 =σ𝑖=1𝑛 𝑔𝑖∙𝐻𝑖∙𝑚𝑖∙𝛹𝑖

𝐴= 2893 ൗ𝑀𝐽

𝑚2



ASSESSMENT OF TIME TO ESCAPE (PD7974-6:2004)

HP:

• Occupants: familiar and awake

• ta= 150s

• Activity not strategic

• 5 occupants

Rvita= A3 (according to D.M. 3/08/2015)

Rbeni= 1 (according to D.M. 3/08/2015)

One compartment

Alarm level A1

Building level B1

Management level M1

L= 57,5m

Les= 45m

N° EXIT (min) 1

W= 120 cm

20 m

To verify that the length L of exodus path is not greater

than the maximum length Les

37,5

m

The adoption of additional measures can increase the

maximum value of the path length.

𝐿𝑒𝑠,𝑑 = 1 + 𝛿𝑚 ∙ 𝐿𝑒𝑠 𝛿𝑚 =

𝑖

𝛿𝑚,𝑖

Les,d = 67,5 m



ASSESSMENT OF TIME TO ESCAPE (PD7974-6:2004)

CASE tdet

(sec)

tal

(sec)

tpre-mov

(sec)

tperc

(sec)

RSET

(s)

RSET

(min)

1 150,01 0 60 47,92 257,93 4,29

∆𝑡𝑒𝑣𝑎𝑐= ∆𝑡 )𝑝𝑟𝑒(99𝑡ℎ 𝑝𝑒𝑟𝑐𝑒𝑛𝑡𝑖𝑙𝑒 + ∆𝑡 )𝑡𝑟𝑎𝑣(𝑤𝑎𝑙𝑘𝑖𝑛𝑔

tdet : the moment in which the fire reaches 1 MW and it produces smoke and flames

such as to be perceived by the occupants

tal : the level A1 was assigned to the alarm system, so the delay is equal to 0

tpre-mov : depends on behavioral scenarios that are function of the management level

(M1, M2, M3), the building level (B1, B2, B3) and the alarm level (A1,A2,A3)

ttrav: calculated according to walking speed equal to 1,2 m/s



Source: PD 7974-6:2004 The application of fire safety engineering priciples to fire safety design of buildings. Human factors. Life safety strategies. Occupant evacuation, behaviour and condition (Sub-system 6)

FDS+Evac MODEL: RSET

DET_EVAC_DIST=0,DET_MEAN=150.01,

PRE_EVAC_DIST=1,PRE_LOW=5.0,PRE_HIGH=60.0



RESULTS

Evacuation starts after 190,01s

The last occupant leaves the

compartment after 228s

0

1

2

3

4

5

6

0,00 50,00 100,00 150,00 200,00 250,00 300,00

n°

occ

up

an

ts

t(s)

Egress

The fire is still in the development phase

HRR(t= 228s) = 3,24 MW

0,00

500,00

1000,00

1500,00

2000,00

2500,00

3000,00

3500,00

0,00 50,00 100,00 150,00 200,00 250,00 300,00

HR

R (

kW

)

t(s)

HRR



COMPARISON BETWEEN ASET AND RSET

Advanced Method According to D.M 3/08/2015, point M.3.3.1

• Toxic gas model FED (Fractional Effective Dose) concept: calculated by

default using the gas phase concentrations of O2, CO2 and

COValue far below the incapacity

and death (FED = 1)FED MAX = 7,93 ∙ 10-9

• Irritant gas model Not considered

• Smoke obscuration model Relation visibility – smoke density

The visibility conditions at the human

height do not change from the start

of the evacuation to the end (30 m)




Advanced Method

• Heat model Simplified method: Radiation on occupants ≤ 2.5 kW/m2

Temperature ≤ 60 °C

ASET = 30 minutes

z=1,6 m

Tmax = 22,5 ° C




Advanced Method

y=15 m

The high temperatures are

reached next to the ceiling.

At the moment in which the

occupant passes near the

ignition point, the temperature

is not dangerous to human

safety.




Simplified Method

The ISO/TR 16738 allows using the hypothesis of “exposure zero”. This method

adopt the following performance thresholds:

The height clear of smoke is 2 m

The mean temperature of the layer of hot smoke is not higher than 200 °C

ASET >> RSET



CONCLUSIONS

Fire is a complex situation, whose consequences depend strongly on

the occupants’ characteristics.

Understanding how the humans respond to an emergency, and how

the agent-agent, agent-environment and agent-fire interaction

manifests, can increase the probability that fire simulation is very

similar to reality.

A complete theory of human behavior can be used in performance-

based regulatory systems, computational models, fire safety

engineering design, fire safety education and management.

The simulation with FDS+Evac, object of this study, has the RSET

results similar to those obtained according to the PD7974-6:2004.

The availability of a greater number of actual input data and the

capabilities of fire modelling to simulate the environmental conditions

will make in the future the evacuation modelling even closer to reality.



THANK YOU FOR YOUR ATTENTION



Monica Capobelli, PE

Chiara Crosti, PhD, PE

Konstantinos Gkoumas, PhD, PE

[email protected]

[email protected]

[email protected]

mailto:[email protected]



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