HUMAN BEHAVIOUR IN FIRE 

- Understanding Human Behaviour 

For Better Fire Safety Design = 

znd International Symposium 

March 2001 

Cambridge, Boston (MA), USA 

Trscien3 oommunlcatlonm 

London, UK 
445 

EVACUATION SAFETY FOR LOCOMOTION 

DISABLED PEOPLE 

Anna Brand, Malin Sorqvist, Pia HIkansson & Jan Erik Johansson 

RaddningstjHnsten Vastra Blekinge, Sweden 

SUMMARY 

People are most of the time expected to evacuate by themselves in an emergency situation. 

The design of escape routes today does not make it possible for all people to do so. To 

investigate the safety of locomotion disabled people, in case of an evacuation, a serie of 

experiments were conducted. The experiments were performed to identi& and quantifi factors 

that can influence the evacuation for locomotion disabled people. The aims of this study were 

to investigate both the locomotion disabled peoples possibilities to evacuate by themselves, 

and the fire departments possibilities to assist the locomotion disabled. 

BACKGROUND 

A bill proposed by the Swedish Government (regeringens proposition 1999/2000:79), once 

again, brought the question of disabled peoples safety in case of an emergency evacuation 

into daylight. A fire department in the south of Sweden (Raddningstjansten Vastra Blekinge) 

got a request whether it was possible to have classrooms for disabled people on the second 

floor, in terms of egress. Together with the Swedish Rescue Services Agency the fire 

department started a project concerning locomotion disabled peoples possibilities to a safe 

evacuation. 

The project only included locomotion disabled, able-bodied and only public buildings were 

studied. All of the locomotion disabled were older than 15 years and unassisted. 

Participants were fire safety engineer students, fire safety engineers, an accessibility 

consultant, a human behavior scientist, an organization for disabled people 

(Handikapporganisationerna i Blekinge), a fire department (Raddningstjansten Vastra 

Blekinge), the Swedish Rescue Services Agency, the Department of Fire Safety Engineering 

at Lund University and voluntary locomotion disabled people. 

CONDUCTED EXPERIMENTS 

To investigate locomotion disabled people’s safety . in case of an evacuation, several 

experiments were conducted. Factors that might influence the evacuation time were studied in 

five experiments. In total 90 volunteers participated in one or more of the experiments, out of 

these 50 had different locomotion disabilities. 
446 

In the experiments the participants were divided into four different categories: 

Category 1) able-bodied 

Category 2) ambulant with locomotion disability 

Category 3) manual wheelchair user 

Category 4) electric wheelchair user 

To get a reference group, category 1 able-bodied, were studied. This group is usually used 

when dimensioning escape routes. 

Escape route 

This experiment was made to investigate locomotion disabled peoples possibilities to 

evacuate by themselves. Factors such as movement speed up and down ramps and on 

horizontal ground were examined as well as the time and space needed to turn. The influence 

of threshold heights and the needed opening force to pass through a door were also 

investigated. 

A total of 48 people participated in these experiments, 12 from category 1, 9 from category 2 

12 from category 3 and 15 from category 4. 

In an evacuation situation it is crucial to be able to change direction while evacuating. Most 

escape routes involve corridors and to investigate locomotion disabled peoples possibilities to 

change direction, the participants were asked to turn 180 degrees. The results are shown in 

figure 1. 

- 

Space needed to turn 100 degrees 

- 1.5 

0.5 

2 3 4 

Category 

-_ 

Figure 1 Space needed to turn 180 degrees 

Movement speed up and down a ramp and on a horizontal surface was examined as well as 

the time needed to turn 90 degrees. The ramp was 1,2 meters wide and six meters long, the 

inclination was 1 : 12. Movement speed on a horizontal surface was measured over a distance 

of 31 meters. The width of the turn was 1,2 meter. Results of the movement speeds are 

depicted in figure 2, 3 and 4. 
447 

~- ___. 

Movement speed down the ramp r - --1 - I 3r------ __- 

OJ J 1 2 3 4 

Catogory 

___ 

Figure 3 Movementspeed down the ramp 

Five out of the twelve participants using a manual wheelchair found the ramp to londsteep 

and therefore failed. Down the ramp three out of the twelve participants using manual 

wheelchair failed. In figure 2 and 3 they are denoted as having a speed of 0 meters per second. 

The average movement speed for the ambulant locomotion disabled is the lowest, it is about 

half the speed of the able-bodied. 

___ - r--- Movement speed on horlrontal surface 

- -1 

3 4 

C8tOQOry 

___-_-__ 

Figure 4 Movementspeed on horizontal surface 

The influence of threshold heights and the opening force needed to pass through a door by 

pushing it open were investigated. In this experiment only locomotion disabled participated 

because it was their possibilities to pass through a door that was of interest. In total six 

experiments were conducted for each participant with opening forces of 40 or 130 Newton 

and threshold heights of 0, 2,5 or 4,O centimeters. To pass through the door the participants 
448 

Category 

3 

did not have to push down the door handle. Both the threshold height and the opening force 

caused problems for the participants as shown in table 1. If the participant did not manage to 

open and pass the door by him-herself it was classified as a failure. 

Threshold Opening force (N) Number of Number of 

height (cm) participants failures 

0 130 12 2 

3 

3 

2s 40 12 3 

275 130 12 2 

3 

3 

4 

4 

Some of the participants who were using walking frame and manual wheelchair had problems 

when they had to maneuver, move their aid forward and at the same time open the door. 

4 40 12 7 

4 130 12 6 

4 40 4 1 

4 130 4 1 

Evacuation aided by firemen 

This experiment was conducted to assess how firemen best could help manual wheelchair 

users in evacuation situations. The evacuation route included stairs up and down, a corridor 

and 90 degree turn. Three experiments were repeated eleven times with different participants. 

In the first experiment two firemen assisted a person sitting in hisher wheelchair during the 

whole experiment. In the second experiment two firemen assisted the manual wheelchair user 

by carrying himher through the evacuation route. In the final experiment one fireman assisted 

the wheelchair user sitting in hisher wheelchair through the evacuation route. 

The results imply that, due to the time aspect, if the escape route contain stairs it is better to 

cany the evacuee out. In horizontal escape routes without narrow passages no time is gained 

by carrying, instead of pushing, the manual wheelchair user. There was no relevant time 

difference between the first and the third experiments. After the evacuation the fireman who 

evacuated the wheelchair user by himself was more exhausted than the two colleagues were in 

the first experiment. 

Evacuation by elevator 

This experiment was made to investigate the possibilities for mixed populations to evacuate 

by elevators. Only the time aspect was studied. It was conducted two times with two different 

populations. In both of the experiments a total of 33 people participated. In the first 

experiment only people from category 1 and 4 was represented, one third from the latter. The 

second population included people from all four categories. The time was measured from 

when the first person entered the elevator until the last one did exit the elevator one level 

down. 

It took about six minutes for the first population and nine minutes for the second to evacuate. 

In the first experiment the population knew each other and was familiar with the elevator. 

This first experiment was also well organized, thus leading to a more efficient use of the 

elevator. 

Evacuation by elevator is time consuming. It takes time both for the elevator to move up and 

down and for the evacuees to move in and out of the elevator. Locomotion disabled people 
449 

often need more space than able-bodied in elevators due to their aid. Many of them also need 

both time and space to maneuver in and out of the elevator. 

Movement through passages 

To investigate the occupant flow through passages this experiment was conducted. A mixed 

population was studied while moving through passages of difterent length and width. The 

width was 1,l or 0,8 meter and the length was 1,l or 0,02 meter. The occupant flow was 

studied both for populations consisting of only able-bodied, only locomotion disabled and 

mixed populations. The occupant flow for mixed populations, with different proportions of 

locomotion disabled people, was also studied in a passage with a length of 1,l meter and a 

width of 0,8 meter. 

The flow through passages decreased when the percentage of locomotion disabled people in 

mixed populations increased. The decrease was linear and in figure 5 the results from the final 

experiment are shown. Neither the width nor the length of the studied passages had 

substantial influence on the occupant flow of mixed populations in conducted experiments. A 

single slow individual could delay the evacuation completely or partly for the rest of the 

evacuees. 

- - ---_ll---l_____---__ .. __ 

Occupant flow with different quotes of locomotion 

disabled people 

I 

__ ___ 

_______ % 

o 0,8 - E 0,6 -- 

3 0,4 -' 

F 

-__- 

10 20 30 40 50 60 70 80 

Quote of locomotion disabled people (%) 

-I_- ___ __ 

Figure 5 Occupantflow 

Evacuation by ladder engine 

Another set of experiments did investigate the possibilities for the fire department to assist 

locomotion disabled people from floors above the ground level by ladder engine. Previous to 

the experiments a short education in carrying-technique was carried out to avoid injuries both 

on the participating firemen and on the disabled people. 

The experiment was conducted two times, each time with a different set of firemen and 

participants. Different ladder engines were used in the two experiments. The participants were 

evacuated from a balcony on the first floor. The ladder engine was in place ready to start the 

evacuation when the experiment begun. 

In both experiments ten locomotion disabled people participated as well as ten able-bodied. 

All four categories were represented. 
450 

It took 30 respective 40 minutes to evacuate the ten locomotion disabled. Not all locomotion 

disabled people was able to stand on their legs and therefore they had to sit while being 

brought down. The evacuation of the ten able-bodied took two respective ten minutes. 

The evacuation was both personnel intensive and time demanding. The personnel had to help 

the evacuee both in and out of the basket. The firemen, who participated in the experiments, 

stated that they had use of what they had learned in the previous education in carryingtechnique. 

PROBLEMS THAT MAY OCCUR 

In evacuation situations where locomotion disabled people are involved several specific 

problems may occur. Before trying to lift and carry a person sitting in an electric wheelchair it 

is important to remember to turn the wheelchairs electricity off. It is also important how to 

carry locomotion disabled, when improper carrying- and lifting technique may lead to 

spacticity and injuries. All straps and belts, which may hold the person in an upright position 

in the wheelchair, must be unloosen before trying to lift the person from the chair. 

CONCLUSION 

The evacuation situation for locomotion disabled people is complex. Ability and possibility to 

evacuate varies from one person to another and from one day to another. When dimensioning 

escape routes it is important to take individual differences among the population into 

consideration. No single solution will provide the whole population egress opportunities. A 

combination of different solutions will be required.