experimental behaviour of human in smoke filled corridor

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Experimental Study of Human Behavior

in Smoke Filled Corridors

TADAHISA JIN and TOKIYOSHI YAMADA

Fire Research Institute

Fire Defense Agency

Ministry of Home Affairs

3 14 1 Nakahara Mitaka shi

Tokyo

8 Japan

STR CT

An

experimental

study was conducted in order to clarify a degree of

human emotional

ins tabil i ty

under smoke condition. Mental

ari thmetic

and

walking speed were

adopted

as indices

of t he emotional

instabi l i ty and

furthermore an annoyance of smoke and heat was inves t iga ted by

quest ionnaire . The

emotional

ins tab i l i ty caused by physiological

factors

such as smoke i rr i ta t ion i s found to be important

as well

as a

psychological unrest under high i r r i t an t smoke Such f ire smoke affects

the

thinking power and walking speed. Especially the heat from smoke is

found to reduce the thinking power in the range

between 2 030

kcal/m

h

and

1 370 kcal/m

2

h

INTRODUCTION

A smoke obs truc tion aga inst safety evacuation has been pointed out

through many f i res in the past . High level of carbon monoxide gas

density

and d efic ien cy o f oxygen in f ire smoke

are

main

physiological

fac tors to decide l i f e or death. However physical

and

psychological

effects of thinner smoke a decrease of visibi l i ty through smoke and/or

smoke i r r i ta t ion for

instance

tend

to

panic the evacuees and indirectly

lead to death.

Many

experimental

studies of such

smoke

effects

have

been conducted

in

our

laboratory

with

the smoke of normal temperature.[1 2 3 4]

However in

these experiments

hot smoke

effec ts

on a human

emotional

ins tabil i ty

were

not

considered.

Therefor

an

additional

experiment was

conducted to

clarify

complex

effect of

smoke

and heat usIng

electric

heat radiator .

Subjects were exposed to

smoke

environments in a corr idor and in

each

experiment the

physiological

and psychological effec ts of smoke

and/or heat

radiation were investigated w ith mental

arithmetic walking

speed and questionnaire.

METHOD

N

CONDITION

OF EXPERIMENT

31 subjects part icipated in th i s

experiment.

The

experiment

was

conducted

in a smoke f i l led corridor. Each s u ~ e t was asked

to

walk

FIRE SAFETY SCIENCE PROCEEDINGS OF THE SECOND INTERNATIONAL SYMPOSIUM pp

511 519

511

Copyright © International Association for Fire Safety Science



electric heater

answer

point

return back

forward ; : i

~ ®

@

~

~ ~

distance 2 ;8m 5:

3m

6:9m 8: 6m

10.

~

FIGURE 1 Outl ine o f exper imen t.

forward

in this

corridor

while

doing

simple

additional

and subtractive

calculations as shown in

Fig.

1

Experimental condition of the

corridor

The experiment was conducted in a stra ight corridor of about 11 m

depth 2 5 m height 1.2 m width. On i t s f loor f ive mats in

which

an

on-of f switch was

equipped

were set

to

indicate where the

subject

was

to stand.

At each of

these f iv e po in t s sub jec ts

were a sked

to answer

arithmetic

questions

as

mentioned

later .

The corridor was f i l led with white smoke

generated

by

smoldering

Japanese

cedar crib chips

in

an e lec t r i c furnace

before

star t ing each

experiment. At th e beginning of the ex perimen t a smoke

dens i ty

expressed

by the extinction coefficient

adjusted

to 1 2 and was

weakened slowly to the 0 1 during 30 minutes. In th is 30

minutes

duration two or three subjects

entered

into

the

corr idor individua lly

under various kinds of smoke density conditions.

Temperature inside

the

corridor

was about 20°C At the inner

point

of A and B the heat was radiated

to

subjects with an electr ic radiator

at

A

-->12

Kw

B

-->3

Kw

installed

a t

a

ceiling.

A

maximum

heat flux

density was 2 030 Kcal/m

h

a t

A-point

of 1.5 m height from

the

f loor

l eve l

and 1 370 Kcal/m

h

a t

B-poin t o f the same height . Mean Radiant

Temperature

measured

with

a

glove thermometer

was about 82°C

at

A-point

and

75°C

a t

B-point.

The

inside

of the corridor was illuminated by fluorescent lamps

and

the

i l luminat ion on

the

f loor

l evel

were in the range of 30 Ix

to

100 Ix. The walking speed between each

answer

point was

estimated

with

mat switches

as

reference dat a rep re sent

the

emotional ins tabil i ty .

Mental

arithmetic

In

th is

experiment

a

mental

ar i thmet ic

method

was

adopted to

estimate

the degree of emotional instabi l i ty under smoke

condition.

The

rate

of correct answers to simple

arithmetic questions

was expected

to

5



decrease continuously with

increasing the human

emotional inst bi l i ty

to

a cer t in

extent. This r te

was therefore adopted

as

an

index of the

emotional ins tabil i ty .

The mental arithmetic

questions

were

recorded in

an

endless tape

and 10

questions

were

continuously

addressed

to the

subject by a loud

speaker

t

each

f ive

answer

points (A

to

E).

Three

kinds

of

question

in te rv l speed, 1.5 sec. /quest ion for male and 2.0 to

2.5

sec. /quest ion

for female, were selected

to compensate

for individual difference.

This set of

10

questions

was

repeatedly given

with

an

interval of

10

sec.

The

subject

was

asked

to answer the quest ions

t

each answer

point. After

answering the

questions t

one point,

they were

asked to

move

to the

nex t d eepe r

posi t ion during th is

10

sec. in te rv l This

action was

repeatedly

conducted to

the deepest

A-point. The answers

were

voice recorded

in a handy

type tape

recorder

and

were

rated after the

experiment.

These data

were

normalized

by an average correct

r te of

90

questions

under

normal condition, without

smoke and

heat

radiation, to

compensate for

indiv idual d ifferences

of

calculation abil i ty .

Subjects

31 adul ts

aged

20

to

51

male 14, female 17)

p r t ic ip ted

in

th is

experiment.

These

females were mainly house wives and

males

were

universi ty

students.

Before

the

experiment,

no

detailed

information

of

the

corridor

were

given and the corr idor s t te without

smoke

was not displayed.

The

subjects

were

only told

that

this was an

experiment

concerning safety

and

were

given

fundamental instructions, Le.,

a

corridor f i l led with

smoke

is

st r i t

and has an end and

subje cts a re

allowed

to

return

back

whenever

they

want

to.

The

subjects

were

protected

from

smoke i r r i t t i on with

a 16

layered towel

on

thei r

mouth and nose.

As

proven

in

a

previous

experiment, th is towel protected the subjects from

90

of the

smoke.[5]

RESULTS

N

ONSIDER TIONS

Interruption of

experiment

At

the beginning of each experiment, th e conditio n

of

the

smoke

densi

ty

was

not the same.

The

val ue s var ied in the rage of

Cs

0.92

0.21

1/m. In

f i r s t

experiment

t r i l

with th icker smoke,

17

subjects

male 6, female 11) could reach

the

deepe st A -point,

and other

14

subjects male 8, female 6) returned

back

with interruption.

Fig.2

shows

a

re l t ion

between

an

t t in ble

dis tance

and

the

c o r r e c t answer r te

of

the

l t t e r

14

sub j ec t s

Seven

subjec t s

interrupted their

waLk

t the nearest

E-point

(2.8 m from

entrance)

and

the correct rate fe l l

down

to

about

7

of the normal cor re ct r at e. Six

out of these seven

subjects interrupted

again in the second t r i l under

5



10

under the condition of

Cs 0.92 ± 0.21

11m

6

o

7

per-s ,

0_\/ -

o

l\

0

1

P, , .

0 ::0

0

pe r s ,

o J per s .

2

j

->

oj

H

H

j

60

jJ

oj

o

j

40

H

0

o

j

20

-

. .

oj

j

p::

0

0

Distance from entrance m

FIGURE

2. Relation

between

distance from entrance an d

correct

answer

r a t e : 14 subjects 8 males, 6 females) returned back with inte r r uption.

c o n d i t i o n o f Cs = 0.66

m an d

moreover two o f them d id

in th e

th i rd

t r i a l Cs =0.62).

In

the f i r s t t r i a l under thick smoke, three subje c ts turned back at

D-point

5.3 m

distance

from

entrance), o t h er three

a t

C

-point

6.9 m ,

one at B-point 8.6 m , and

the

each co rrect answer

r a t e

was about 35

and 75

.

The

co rrect

ra te decreases when the subjects returned back

e a r l i e r , t h a t

is ,

th e e mo tio na l instabi l i ty

is

l arg er when the subjects

returned

back

ear lier .

Correct

answer r ate

and emotional instabi l i ty

Some s u b j e c t s were

ab le

to re a ch th e en d of th e c o r r i d o r i n

the

f i r s t t r i a l

under

th icker smoke. A sol id l ine

o f

Fig.3 shows the

re la t ion between

th e

a t ta inable

d i s t a n c e from

th e

e ntr a nc e

and

the

c or r e c t

answer

r a t e .

This

average

rat e

of

17

subjects

fal ls

down

a t

the

l o w e s t jus t af te r e n t e r i n g th e c o rr i d o r a t

E-p o i n t )

and

i t

t e n d s to

r i s e

up a t deeper

points.

However,

in

inqui r ies conducted a f t e r

ex p eri m en t ,

the s u b j e c t s

p o i n t ed

ou t

tha t

they

f e l t more

u n r e s t

when t h ey

walked

forward.

Experimental r e s u l t s of walking speed

as

mentioned

la te r

support the

va l id i ty of

th ese

ind ica t ions . From

th ese

fac ts ,

th e

re la t ive correc t

rat e

caused

by

psychological

fact o rs

is considered

to

d ec re as e u nd er

a

cert ai n conditions, which

is

unknown

in

t h i s experiment, when subjects

walk forward as shown in

Fig.3

with long dashed l i n e.

From

the

view point of physiological aspects, the

abrubt

decrease

of correct

rat e j u st a ft e r entering the corridor

ca n

be explained by the

smoke which a tta c ks

the subject s

eyes and throat. As

this discomfort

is l ightened

with

the lapse o f time,

the

co rrect answer rate may r i s e

when s u b j e c t s walk

forw ard as

shown

in

Fig.3

w i t h

dashed an d d o t t e d

l i n e. The heat r a dia tion e f f e c t

i s

involved a t A and B-point.

5



The

obtained

experimen

ta l

data

as

shown

in

Fig.3 wi th s ol id l in e

appears

to

be composed of two kinds of smoke effect , the physiological

and

psychological

ef fec t

on

subjects .

The re la t ion between these

two

effects

i .e. , whether

a

simple

algebra of

addition

can

explain

the data

or

not,

is a task for further inves tigat ions.

Heat

flux

effect on correct answer

rate

Fig.4

presents

the mental ar i thmet ic

resu l t s

under no smoke

condi t ion. The data a t A-point d rop to 10 lower than those

of

other

points. This

decrease

is caused by the

heat

radiation from an electric

heat radia tor ins ta l l ed

a t the

ce i l ing

The same drop a t A-point i s

also apparently recognized under smoke condition presented with normal

line in

Fig.3.

Nevertheless, no

fa l l is

found a t

B-point.

100

(j)

m

H 90

H

Q)

::<

CIl

@ 80

->

o

(j)

H

H

o

o

(j)

:>

M

m

H

Q)

~ 1 psychological effect presumption

~ 2

PhySiological....... °

~ ~ f f t p r e s u m P t ~ : : L

\ ......... °

.?O- o<-obtained da t a . « 1 + 2 ?

°

0

under

on ition

of

smoke density

Cs

=

0.92

±

0.21

(11m)

0

2

4

6

8

10 12

Distance

from

entrance

m)

IGUR

3.

Relation between distance

from entrance and correct answer

rate:

17 subjects 6 males, 11 females reached a t the end of corr idor

in

f i r s t

t r ia l

~

100

Q)

H

H Q)

g

90

H

Q)

:> H

M (j)

80

H >

Q)

m

cc;

1,370

kcal/m

2 h

......... t:l _ ... t:l.._- t .. _.-Q:

E

e

*

-point

2,030 kcal/m

2 h

2 4 6 8 10 12

Distance

from

entrance

m)

IGUR 4.

Relation

between distance from

entrance

and

correct answer

rate

with

e lec t r i c heater and without smoke: the e lec t i c heater is

instal led a t A and

B-point.



1 5

o

male

)

*

J)

*. female

~

1 0

*

d

* ~

)

fh:::

o ..:::ii

~

)

o,

@ ~ } 0 3

Cs ;;. 0 6

J)

0 5

.....

.......___

i}

0 9 ; ;

Cs

; ;

1 2

·r

l

oj

00

2

4

6

8

10

12

Distance

from

entrance

m

FIGURE

6.

Relation

between distance from

entrance

and walking

speed

1 5

o

Q)

J)

S

d 1 0

Q)

Q)

p..

J)

0 2 0 4 0 6 0 8 1 0

1 2

Extinction coefficient Cs 1/m)

FIGURE 7. Relation between

smoke

ex ti n t ion oe f fi ien t and walking

speed

condit ions

and

methods

The

use

of a towel

to

prote t

f i re

smoke

in

th is

experiment

seems

to

be

the

main

reason

About

90

of

smoke

are

removed

with this

towel

and

i t lessens the

smoke

i rr i t t ion effect

INQUIRY

RESULTS

Some

questions

were

asked to each subject f te r

the

experiment

One was a

question

on

uncomfortable

fac tors of

smoke: What

are the

uncomfortable factors

of

smoke? Select three factors concerned with

fire

smoke from

following

items in order i

Tab.1 shows

the result

Some

variances

between male and

female are

found Physiological

factors

were

mainly selected

by

males

Eyes

and/or

throat

i r r i t t ion

was

the

f i r s t

or

second

selected item Obstruction of

inhalat ion was

se lected

as

the

second

or the th i rd uncomfortable

factor

7



In

comparison

with the above males'

answers,

females

tended to feel

psychological discomfort. The obstruction of vis ibi l i ty was selected as

the f i r s t

cause of discomfort of

females along

with an

i r r i

ta t ion and

inhalation problem. This

obstruction

of visibil i ty was also

cited

as

the second

cause. This

experimental

resul t indicates

that the

emotional

in s tab i l i ty in th ick f i re smoke is not necessar i ly caused by the same

factors

for

males

and females. Under

thin

smoke conditions , th e smoke

i rr i tat ion

and heat

flux are selected

as the

f i r s t

or the second factor

without distinction of

sex.

Tab.2 indicates

the

resu l t s of the inquiry regarding

emotional

reactions

towards radiant heat flux. At B-point, the power of electric

heat

radia tor (about

3 Kw) is too

small

to ra i se the subject ' s

discomfort.

The

answer

was

mainly

just feel

heat

a l i t t le ,

the

other

point

(A-point

with 12 Kw

heater),

44 of subjects

answered

hot but no t

intolerable under smoke condition, however this rate increased

to

50 %

under

no smoke condition. 7 % of

subj

ects answered intolerably hot

under

smoke

condition,

and 29 %

under

no smoke

condition.

In

th is

experimen t, th e

in tensi ty of

heat f lux

on

subjects were

almost the same under thin and

thick

smoke conditions. The surrounding

smoke may psychologically blunt the feeling on heat flux.

TABLE 1. Uncomfortable fac tor of f i re

smoke:

Question Select three

factors

concerned

with fire smoke from

following

items

selection items

male

(%)

female

(%)

1st

2nd'

rd

1st - - - -2nd · · ~ 3 r d

a .

foul

smell

1 ( 7%), 2( 14%)' 3(21%) 1 ( O( 0%),

1

7

f J

b.

smoke

i r r i ta t ion

8(57%):

4 2 9 ) ~

1 ( 7%)

7

(41

:

6(35%):

2(13%)

0

c.

obstruction of inhalaion

5(36%):

4(29%):

5(36%) 4(24%):

3(18%)1

6(40%)

::;::

obstruct ion of v is ib i l i ty

O(

0%):

3(21%):

3(21%)

5(29%)1

6(35%)\

5(33%)

o

d.

}<i

e.

heat

O(

0%):

1(

7 :

O( 0%)

O( 0 1

1 ( 6%),

O( 0%)

0

H

f .

feeling

of i solat ion

O(

0%);

0 :

1

7%)

O(

0 ,

1

6%):

1 ( 7%)

iI1

O(

0%):

O( 0 1

1

7%)

O(

0%):

O(

0%):

O( 0%)

o<

g.

others

I

. ~

__

a. foul smell

2(14%Ji

2(17%):

3(30%)

2(13%): 7(50%): 2(15%)

f J

b.

smoke

i r r i t a t ion

6(43%):

O( 0%)\

2(20%)

3(19%)' 4(29%): 2(15%)

0

c.

obstruction

of inhalaion

3(21%):

3(25%), 4(40%)

2(13%): 1

(7 ),

3(23%)

::;::

d.

obstruction

of v is ib i l i ty

O( 0 ,

1 ( 8 1

O(

0%) O( 0%):

O(

0%):

1 ( 8%)

/

:z;

e.

heat

3(21%)1

5(42%)1

1 (10%)

8(50%),

O(

0%),

2(15%)

H

f .

fe elin g o f

i so la t ion

O( 0%): O( 0%): O( 0%) 1 ( 6%): 2(14%)' 2( 15%)

iI1

O( 0 :

1 ( 8%):

O( 0%)

O( 0%):

O( 0%):

1 ( 8%)

o<

g.

others

TABLE 2. Feeling

for

heat

radiat ion under

smoke and no smoke condition:

Question How do you

fee l

for the

heat flux

on you a t the

deepest

A

poin t?

selected

items

with

smoke

' wi

thout

smoke

1- intolerably hot

2

( 7

%)

I

8

(29

2.

hot but

not

intolerable

13 (44 %): 14 (50

3.

comfortably warm

7

(23 %):

4

(14

4.

just

feel

heat a l i t t l e

4 (13 %):

2 ( 7

5.

no

feeling

4

(13 ,

0

( 0

8



ON LUSION

The

following resul ts

were

obtained

on the

emotional instabi l i ty

affected by smoke from this

experiment.

The

emot ional

i n s t a b i l i t y

in

f i r e smoke

i s caused

by

psychological

and

physiological

factors.

However a

quantitative

analysis

on

the

rat io of

each

factor was not

clar if ied

in

this

experiment.

2. The degree of f i re smoke annoyance

decreases

wi th the lapse of

time.

3. The walking

speed

in f i re smoke

decre ases with

increased smoke

density and

walking

distance from

the

entrance

in the corridor.

4 The

emotional

ins tab i l i ty affected by smoke was found

to

be

different

between males and females

qualitatively.

Whereas males

tended

to

fee l

physiological discomfort

the

psychological

factors

including

the decrease of

vis ibi l i ty

are dominant for females.

5. The

threshold

of the

heat flux

affects

the thinking

abi l i ty

is

in the range between 2 030 kcal/m

2 h

and

1 370

kcal/m

2 h

R F R N S

T.Jin

Vis ib i l i ty

through

fir

smoke J.Fire Flammabi l i ty 9:

pp.135-157 April 1978.

2

T.Jin

Studies

of

emotional

instabil i ty

in

smoke from

f ires

J.Fire

Flammability 12: pp.130-142 April 1981.

3. T.Jin Studies on

decrease

of thinking

power

and memory in

f i re

smoke Bull. of Japanese Assoc. of Fire Science Eng. 32: 2

pp.43-47

1982.

4.

T.Jin

T.Yamada I r r i t a t ing ef fec t s of f i r e smoke on v is ib i l i ty

Fire Science Technology 5: 1 p.79-89 1985.

5 T.Jin Effect of smoke reduction with a wet towel Bull. of Japanese

Assoc. of Fire Sci.

Eng. 31: 5 p.26-30 1981.

9

experimental behaviour of human in smoke filled corridor

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